Unable to be create branches

I am trying to initiate pull request but i am not able to make a branch
I am new to github, any idea for updating my files on this repository

[cclauss]

Are you using git on the command-line or the GitHub web UI?

web UI

Please help me, I have algorithm for 3d vector point to 2d vector point

[cclauss]

Add file... Create new file...

Then type: directory_name/file_name.py

thanks