You can fly your ship, customise it, have space battles etc - I don't think the flying is as intricate as games like No Man's Sky, for example. But yeah, as LBT said its basically a big exploration game with loads of quests and things to do, pretty fun stuff!
I haven't gotten it myself, as Bethesda games are usually best played with performance-improving mods I'm sure the community is working hard on as we speak. But I'm sure I'll get it eventually, any Bethesda game is worth the price because of the entire library of amazing fangames that will inevitably run on its engine, plus infinite mods of any stripe and shape to craft the game into exactly what you want to play.
Alas I'm on xbox so I'll need to wait until they've added mods to it, like for Skyrim and Fallout, but looking forward to those!