For example:
This given command for go to main branch or I can also say that this command is use for changing the branch.

git checkout <branch name in which you go back>

Delete a branch with

git branch -d <branch name>

for creating the new branch in the main or master branch I can use the given command.

git branch -b <branch name>

Done☺
.

IF you want to know more how to contribute on the opensource code on github