I've noticed companies post lists of requirements for an intern role but they expect them to do everything that would be required by a particular role as an employee from day one.
This is usually done to save on the cost as they offer a much lower salary and sometimes no salary at all.
Is there anything that can be done legally against such companies which exploit candidates? What is the actual difference between internship and job and how can one convey this message to HR?
In theory, at least, during an internship the company spends resources to train you to become an effective (and efficient) employee. It is assumed that you are not very useful to the company during the internship, as you do not know how to do things.
On the other hand, if you are with a company as an employee, you are expected to know what to do and that you can bring profit to the company.
Of course, reality may prove different than theory, but that is a different story.
First of all, if you see any kind of job as an exploit don't do it at all, to save your time (and your employer's time as well).
The internship is usually a limited job for a very short time period. (Maximum is about 6 months). Internships are not bad, especially when you are a student. Keep in mind that it costs time, money, and productivity to get the new members involved in the current team. And also it takes time for the rest of the team to train you and help you understand the ongoing job.
What is the actual difference between internship and job and how can one convey this message to HR?
They already know the difference much better than any of us as to how it pertains to the individual company scenario, no need to explain.
To actually answer your question
Is there anything that can be done legally against such companies which exploit candidates?
If you were capable of doing the same thing you would not be applying for an internship, you'd be applying for a job. An internship is for training purposes. They're not exploiting candidates they're just looking to train people or find someone fully trained who is stupid/desperate enough to apply. They don't force you into signing a contract, you can reject it if you're not happy with the pay or the terms. If you have to do the exact same thing as people full time, why don't you apply for the job instead?
Can you do anything legally?
No.
I've noticed companies post lists of requirements for an intern role but they expect them to do everything that would be required by a particular role as an employee from day one.
This is simply not true. This is what you are going to be doing at some point during your internship. Once trained and on the level of where you can do more advanced things it is correct that you may be doing a similar if not exact same thing for less wage.
