From here this looks like a Visual Studio setup issue, not a subject that comes up here.
Here are three things to check:
1) A little Googling suggests this may be the related
So check that this is the only Python in Visual Studio (or is the Python actually used)
2) Visual Studio Code python version are the same.
Check not just the version, check that they are really from the same build with python -VV (yes, 2 Vs)
Because MS Python does differ from
python.org Python.
3) Check that 'pip list' shows Kivy installed.
My guess would be door #2 and VS has MS Python, but since nobody seems to use MS Python it is just a guess.
If this is the case an 'import kivy' at the top of the file might get past this issue.
But I do not recommend this workaround as a solution, as I expect similar issues will arise again and again.