Run it with NO fuel and on compression for five minutes, then add fuel. It's cold, it won't start until it's heated. Right at the end, the tractor should have declutched and the engine would have taken off
My father in law sold an engine like this and the people who bought it did this very thing. And it started. The governor was frozen and the engine ran wild, the clutch on the cat engine blew first, shrapnel everywhere. Beware.
By indicating its cold use a rosebud burner down the intake in cycles while it being turned over. That'll help unjam the stuck rings enough to start. Also use the clutch on tge engine that's heavier to take the abuse. That lil tractor won't hold up to that.
Unless the tractor has a reversible PTO, then yes, it would seem so. Intuitively, logic would dictate that both the tractor engine/PTO and slave engine should be rotating in the same direction, however, some engine variants are built for opposite rotation. If we look at what appears to be the exhaust stub, we can clearly see that's where the exhaust gasses are coming from. If the engine was turning backwards, any exhaust gasses produced would be issuing from the inlet manifold. I remember my brother buying a used engine to put into his JD combined harvester, and having to belt start it from a tractor belt pulley in order to obtain the correct rotation. Once woken up from its long slumber, that engine started from its own starter motor and ran perfectly.