How to create a tile library

I purchased asesprite to be able to create maps for a game that runs on 8-bit computers. I saw that it is possible to create a library of tiles that can be reused. I can’t figure out how to do it, there is a tutorial. I found some documentation at this address Aseprite - Docs - Tilemap, but it wasn’t useful to me. Do you have any suggestions?
Thank you.