Answer 1

Are you trying to import / export components from different SoloLearn projects?
It doesn't work like that. Projects don't share files.
Web projects have 3 tabs (windows): HTML, CSS, JavaScript. This is it. They are connected. You can't add more files.

Basically, you have 2 choices:
1. Put all your components in 1 file (it may become hard to read/edit)
2. Use github and separate components like you normally do.

Here's one of my complex react projects. I use github for code, vercel for hosting and a SoloLearn project to show everyone the result of my work.
https://code.sololearn.com/WaDjl5Pbb2iL/?ref=app