In interviews for a new company (not the client), can I mention about the unethical practices of the company when they ask "Why did you quit ?"?
Yes, if asked directly, you should respond directly: "you felt uncomfortable in the previous role as you were being misrepresented to their clients and were allocated work that was grossly outside of your experience." Follow that up with something like "I am seeking a role where I feel valued for my experience have the opportunity to become a key contributer".
How can I make sure that the unethical behavior of the current company does not in any way hamper my career?
It really shouldn't affect things in the long run, you could omit the experience at all from your CV, listing the short term role will raise a few questions but if you are honest and stand up for your personal values then this can be easily turned around into a positive.
I would suggest that in your case, you are right and justified in quitting. It will not help you as a person to work in a dishonest or non-supporting environment, toxic work environments make some people stronger, but many will feel chewed up, will not have learnt the skills necessary for their next role and often lack self confidence. If you don't feel comfortable, then get out, there are so many other jobs out there.
A key element of the interview process is that you are assessing the client as much as the client is assessing you. Even if you have pressure to make sure you win the job, your job throughout the interview is to ascertain if you or your company has the ability to fulfil the requirements of the client.
If you have a team to help you, you still must remain honest, but you are not just representing yourself, you are offering the experience (to a degree) of the collective. If you (with the support of your team) do not have the knowledge in a particular area, call it out by saying something similar to "I haven't directly worked with that
<insert framework here>, but I have worked with
<insert something similar> and I have a team behind me that can assist if I need to bounce some ideas". It's not a lie, but in some cases it might be reassuring enough to the client to get the job. In this case you are doing the right thing by your client and your employer.
- the right thing swings both ways, if you secure a contract but are later unable to fulfil it, then that will be bad for you and for business, either it will end in non-payment or some form of compensation, so there is no value in winning a job that you know cannot be serviced.
If the only issue is 2 vs 4 years experience, but you do work with Java day to day and you do have the support of your team to fall back onto, then from the client's point of view, you really have the combined years of experience from your team behind you. It feels wrong on one level, but if you legitimately have access to the rest of your team, as well as a personal drive to learn and improve your Java then that should be enough for what the client requires in many cases.
I would have the negotiation with your employer, "If I get this, you need to make sure john will be available to back me up" (where John is the guy who actually has the 4 years experience.)
If there is no such support or experience at all and you know it is required for the project then just shut that down, you could mention that your experience is limited to general help desk, evaluating stack traces and locating and logging issues. That might be a lie, but it will send the right message to the client.
You can use other phrases to play it down if asked directly, like "on and off" or "when required" These can be red flags when the client hears them, keep in mind the client knows that just about everyone exaggerates on their CV, even to the point where if you haven't listed some elements, that is more telling than the fact that you included it in your CV at all. After working for 20+ years in the field, 2 vs 4 years is not a lot, sure it's double, but not significantly enough to warrant concern, as long as you personally have been working in computer science industries for 4 years. (that's only 2 rounds of COVID-19 lockdowns in Melbourne ;) )
I don't condone outright lies; just make sure you do not over commit to what you with support could achieve. If you need to avoid blame being attached to you then just be honest when asked if you can do something or not. Tell the client if it is new if you are interested in it, or if you are not, why not. If you only have 2 years and they are expecting 4, suggest that you worked with it solidly for 2 years, but recently have focused on something else.
It is a balancing act, and I know that I'll attract a few downvotes for this, but there is a lot of value in the fact that you are working as part of a team. That is often a cheaper source of experience than many clients are willing to pay for. Just keep it honest and when the questions get hairy, fall back to the "team" speak.
If your supervisor has that level of faith in you, take comfort in that, this is probably an assessment that they make often. They have decided that you can do this and your worth is similar to what a client who is asking for 4 years of experience should be able to expect. You will be forced to jump into the deep end every now and then. Your supervisor thinks you are ready for this.
If you know that you cannot achieve the client's requirements and you do not want to be held liable, but you want to do the right thing, then you can throw the interview either by being deliberately vague when asked specific questions or keep redirecting the questions to a response that you know is opposed to the client's requirements, perhaps by overemphasising a vendor the client does not agree with. In this case if they still pick you, they have made their own assessment that on the balance of everything else, they would still like to work with you. They would still like to invest in you and your personal development.
If/once you get the job, just be honest the whole way. If you do not understand something, then ask for help or clarity. If you need more time, then ask for it. 2-4 years experience is not the same as 2 vs 20 years. Be open in your communication and let the client make up their own mind as to your success in this role. If it fails, learn from it and move on. The interview is only the start of the relationship, if you keep everything honest from your part, you will only be held liable for how you conduct yourself as you complete the work.
If they pull you up on lack of experience, just say that you haven't come across that particular scenario before. That happens a lot and is acceptable.