[help]import object into game

hi everyone :D
1- can anyone tell me how to add house or bridge that i already designed on blender into game i already knows how to make it into nx3 but then what :/
2- how to read cob files and edit it :/

any hint :) ?

There are 2 ways to edit cob files, Either with a hex editor or Stool.
Although I'd highyl recommend just getting Stool, if you add me on discord Lyza#5923
I'll send it to you :)