git checkout -B <your-branch-name>
for example, if I’m working on theme, I would name my branch with my initials (s b) followed by the type of work and title:
git checkout -B sb/feat/theme
Your branch is where you will be pushing your changes as commits, which will later on get merged with the main branch.
3) As you have written your code, you can push the changes to the remote (the version present online on github) repo.
i) stage the changes: git add .
ii) to commit the changes: git commit -m <commit-message>
iii) push: git push origin <your-branch-name>
Then go to GitHub and create your Push Request (PR) by writing the description of your work, and attach some screenshots of your testing.