Put a camera tripod on deck at night. Now, put a stick on the tripod and try to point it at one star, any one star, and keep it pointed exactly at that star.
That's what you have to do for satellite internet, except you'll be pointing a dish not a stick. And anytime it moves off the star--you lose the signal and have to start over again.
Yes, there are portable satellite internet stations used by RVers, you can set them up anytime you run aground. And yes, there are stabilized satellite internet connections that align themselves--you don't want to know the cost per minute, or the cost up front.
Cellular internet is probably as good as you'll get for now, and what you get and what you pay depend on who services your area. Most of the "unlimited" plans also have a
line of fine print: Limited to 5GB per month and no streaming multimedia (
movies, etc.) or they reserve the right to cut you off.