Hello @valkier, thank you for the post, welcome to the forum and sorry for the delay.
The scenario you’re describing is what can be done using folders and their hierarchy.
Have you had the opportunity to check out the tutorials we have up on Youtube?
They might answer some of the questions you might have.
If you need collections specifically, then it is not possible to do this at the moment, but it sounds very similar to this feature request:
Hope this helps,
Yuriy
FontBase Dev Team