scene load order problem on build and sometimes editor runs.

my builds don't load scenes correctly half the time. i think it has something to do with the load order of the hierarchy. sometimes i cant use the mouse buttons or sometimes tab and esc don't work. sometimes the player cant move at all. sometimes a standard cutout material gets switched to standard opaque, prefabs with rigidbodies don't have colliders so on and so forth, is there a way to manually set an ordered list to load a scenes contents from? also is there a way to have the timescale set to 0 while it loads then switch back to 1? (for rigidbodies and colliders to load so they don't fall through the ground)