Take the following steps to upload code:
1) because the branch is written protected, generate a ssh key first toaccess to the repo. Follow https://git.i2r.a-star.edu.sg/help/ssh/README(Generating a new SSH key pair) to proceed with generate new SSH key.
since I have tried several times previous to git add . and git push, theerror
git add .
git pull
the error report "fatal: refusing to merge unrelated histories"
use
git pull origin master --allow-unrelated-histories
to fix the problem.
git commit -m "Add all my files"
git push -u origin master