After fixing coolant issue, it'll prob. Still be stuck. You can clean / soak'm or jack it up , start in gear & work clutch in& out while throttling and or slowly trying to stop wheels, while clutch us pulled in & it'll eventually free up ( might have to do that & change oil a few times tho)
If what you mean by "cant get the clutch to disengage."
is, its sticking & not... slipping.
ie stalls when trying to put in gear