Hi,

Question 1:
Where is the preview for browsing images?
File / Open
Only file names, no preview images.

Question 2:
Where is a simple text tutorial?

Thanks.

Answer 1: I don't think it does this internally. You'd need someone else to confirm this. Any possible solution may be different between Windows, Linux and Mac OS so it's always helpful to state which OS you're using and which version of krita since krita does get updated quite often.

Answer 2: This is well written and presented: https://docs.krita.org/en/