creating a custom structure data pack that only spawns the structure once as a starting structure

first: is this possible? i need to create a datapack that lets you spawn into a starter structure.
second: id like to create a custom structure data pack first, then edit it to work as stated. but i cannot find a tutorial for doing this on 1.21.1!!!!! does any one know a good video?
third: if this is possible then id like to ask: how would i edit my pack file to change it from a randomly generated structure thru-out your world to just a 1 time spawn starter house?