best modpacks for a forever world?

hi everyone, i really want to make a forever world but find vanilla minecraft to be boring. i've had this feeling for quite some time now but most modpacks i play have a very clear playthrough, so im wondering if anyone has any recommendations. the only preferences i have are a questbook which is preferred but not necessary, and absolutely NO serene seasons.

edit: okay so it appears some people dont know what a FOREVER world is, its a world i keep playing and dont start another

https://redd.it/1uq6vsi
@MinecraftModded