There is btw a sub-forum on indoor cycling here.
Paletons are expensive to buy and expensive if you subscribe to their service.
There is a lot to be said for using a virtual platform because spinning away indoors on a stationary bike is boring enough. I'm not a salesmen for anything in the bicycle industry but in my judgement using Zwift or a similar platform is one way to keep it at least semi-interesting. For this reason, that is using something like Zwift, a smart trainer is a good idea. You can buy a Wahoo KIKR Snap wheel-on trainer that you attach your bike to for about $500. Zwift costs $16/month. You would need a laptop or tablet that will run Zwift so look into that. A smart trainer is nice because the virtual program feeds back into the trainer to simulate going up hills.
When you think you have it narrowed down check youtube there are tons of vids for just about everything out there.