The stuff came from outside a spilled drink maybe?
In any case you need a few parts like speakers and there is likely junk stuck under the logic board. This could get expensive if it’s not too late now. Get some cotton swabs and pads to clean as much as you can. Just dampen the cotton so nothing wrings out I would use distilled water or 80% isopropyl alcohol. Don’t use tap water as it’s loaded with minerals and salts which you don’t want.
Review this [guide|124676] as that should help explain your systems construction.