I have an associate degree and with that i obtained a job in a tech company. Now i'm studying a computer science full degree. I'm planning to change my job and my question is if putting that i'm still studying will affect the opinion that employers could have. I'm afraid they could think that because i'm studying i will not dedicate all my effort to my main job.
Your CV will reflect that you're a student and you currently have a job. I cannot see what else you could state without lying or at least bending the truth.
Your position is not as weak as you seem to believe: Despite 'only' being a student, you have been entrusted with a job. That is good at this stage of your career.
Don't worry about whether a future employer will worry about your effort, as you clearly state you are a student; they would expect you to want to complete your degree.
Finding out how much you can contribute is what the interview is for. Perhaps their and your expectations align nicely, perhaps they don't.
One of the best programmers I know was a student, while at the same time being a team lead in the largest software company in my country.
He was 25 at the time, team lead, also teaching programming courses in the company organized software academy that helped thousands of people get their first software job.
He was studying computer science in the local university.
This is common, good people get hided before they get their degree all the time. Depending on the location, there is a chance that your boss and/or some of the interviewers will be students themselves.
There is nothing to be afraid of.
Will it affect me negatively if I put in my CV that I am still studying?
You won't find out until you try, as there is no general rule or standard for this.
That said, if in an organization, you being otherwise eligible for a position, they want to undermine your capabilities just because you're enrolled into an academic course - would you really accept them as your employer? (Note: It's a rhetorical question)