Please help

Btw the model is quest only

So I down loaded a quest model and for some reason it says it has to many polygones and it says it won’t work on quest I can’t fix the polygons because my pc can’t run blender what should I do?

Also another question why when I download a pc&quest avatar the builder says that the avatar is not compatible with quest

Hey I was just wondering idk if I’m doing something wrong or but when ever I import a model into Unity I can only find the prefab model and not the full model?