Does the crack close when you press on it?.
Yes - prise open the crack with a table knife, stuff in as much PVA glue as possible, using another long, blunt thin object to push the glue as deep as possible. Wipe away any excess. Use brown parcel tape to tightly wrap around the repair, this will keep it clamped as the glue dries. Wait overnight. Remove tape and sand.
No - carefully add superglue to the cracks, the glue will get drawn into the crack somewhat.
If there is a hollow sound to the damaged area AND the cracks won’t move when pressed then it may need more experienced hands.
Hope that helps, so long as you don’t cut anything or drill any holes most attempts at repairs are fairly easily reversed.
Good luck.