MacOS how to remove changes that you did not make?

Question

git

installed VSCode on macOS,
Made a clone from git git clone SSH....
Opened the project in VSCode, to make sure that everything was cloned, I registered git pull, he added the changes
Everything, and here is a stupor ..
because I can’t change the branch, because that it says changes have been made and I haven't even done anything yet.

And the essence of the question is how to proceed in order to change the branch?
All changes as in the screenshot, all the same