Hello, hope you are doing well!

First of all you need to contact the previous college/university you were admitted in your first year. Know your registration status there, see if you can still continue in the same college by getting a readmission into the same course of same college. If its possible continue there, if its not get your registration cancelled. Ask your respected college about their unique rules in this regard. Once the cancellation is done, join another college. But the exact procedure in this regard only your previous college can provide you. Please contact your previous college.

You can always continue your studies and finish it. Your age doesn't matter, dropping out, discontinuation doesn't matter. All the best!