Is getting certificate at PCEP important? I am a physics student and I almost finished my third year (I am in sixth semesters ). So I am trying to learn python. I still did not try to learn classes but other than that I know the other stuff in general. I am solving problems at CodeAbbey (currently 80) and at Project Euler (currently 83 problems in there). I am also reading "Learning Python" to improve my skills and learn more about the syntax classes etc.

Next semester I'll apply some places to do an internship. Also, I want to work as an astrophysicist in the future. And as we all know coding is an important skill in the area. Also I' ll go abroad for graduate school. (At least I 'll try)

In this case, is it important to get a PCEP Certificate to show my skills?

Or is it enough if I open a GitHub page and upload my projects/codes?
This is really a matter of opinion, but coding certificates are not widely respected. The problem is that they are generally multiple choice questions and easily crammed for. That is, you can study for a couple of weeks and pass the exams without writing very much code at all. Frankly I've been a Python programmer for well over a decade now and I'd never heard of PCEP. I would much rather see a GitHub repository or contributions to open source projects.

Save your money and spend your time writing more code.