I own a cabin on leased land, but have no written contact or agreement.
Am I liable to pay the Lease? Does the owner of the land have the right to not allow me on the land to get to my cabin? Can the land owner tell me I cannot rent out my home?

I own a cabin on leased land, but have no written contact or agreement.
Am i liable to pay the Lease? Does the owner of the land have the right to not allow me on the land to get to my cabin? Can the land owner tell me i cannot rent out my home? Sure.. if you fail to pay the lease that stops being your cabin... and they can prevent your from trespassing on their land. And any agreement is between you and them... not some third party. Meaning that third party would legally be a trespasser if you paid or not..

If you stop paying, you become a trespasser. Plus your cabin, since it isn't on skids I presume, can become abandoned property given proper notice and time allowed by local ordinance.
Whether you pay rent on the land or not, the landowner can prevent others from tresspassing, even if he doesn't have any written rules about whether you can sublet your cabin.
Basically you sound like you think you have a lot more rights than you do have.