I Cannot Add Extensions to My Project

I cannot add extensions to my project

Did you get any error while upload? can you share any screenshot?

It just redirects me to MIT App Inventor Extensions.

You have to show us exactly what you are doing.

When I try to add extensions from the help section, it takes me to MIT App Inventor Extensions. Should I add the extension from another tab?

That is the Help section.

You import extensions on the Designer view:

I found it. Thank you.