git init
creates git repository
git add .
adds all the file from that folder to github repo
git commit -m "description of commit or whatever"
it does the changes to github
git remote add origin https://github.com/${your github username}/{name of repo}.git
first create repo on github.com and it will give you link of .git file
then with that command you link it up with your project
git branch otherBranch
making branch of project
git checkout otherBranch
selects other branch
git merge otherBranch
puts changes of otherBranch into mainBranch