hi guys,
i am sure there is to much talk about Fillet and Michael Gibson did great work and explain the right way to Fillet but however my small mind can't really understand it ;( i just start using Moi and i really love it so much some time i lost and this because of me not the app however i made this small model for learning and i have small problem with:
1- Fillet this edge please see the attach image.
2- run merge command but same not working with me here.
3- the last question is joint different than merge and boolean union.

thank you in advance and i attach the file