Some basic questions about asset and some suggestions

Hello everyone, I am new here. I want to sell Figma UI templates with the complete prototype.
I am using Unsplash images for screen shorts of my items but not including that in my main file. Are images from the Unsplash website is ok for preview items?
I am using Google material icons in my items. Is this ok to include in the main file? or Should I just use it for preview only?
Can anyone give me suggestions on the Figma file that how it should organize for clients and how should I build documentation?

Unsplash will be fine according to their license terms but you should to check and respect their license terms.

For any assets you should to check the license terms.

this article can help:

Thank you so much. I have read it. What about google’s material icon question?

For any assets you would like to use then you should to check their license terms. if they permit for commercial use (commercial license) then you can use.