Updates were rejected because the remote contains work that you do

hi,
Thanks for your suggestion. I don’t have git knowledge. Can I ask some basic thing, plz? so I opened git bash and what should I do? I assume I shall change the work directory to the right fold?
But anyway, I directly put ‘git pull --rebase origin master’, it comes with ‘git@gitlab.pavlovia.org’s password’. then I entered my password of my pavlovia account, it’s incorrect (show ‘permission denied, please try again’), so I assume it’s the password of the whole pavlovia in git? that impossible to have.

plz, tell me what shall I do.
Thanks in advance!