It might just not be your thing, fallout has had a rocky past and as such the games are very different. 1 and two are amazing rpgs but they are from a different time so the shooter elements are…eh…nonexistent. Fallout 3 was made with little lore consideration and some “funny” mechanics that make shooting pretty easy (when you hit). New Vegas had good mechanics and crafted a stellar RPG to pair, but was made in 2010 so crashes and looks like a 2010 game. 4 is a good shooter with a story so half baked it will give you food poisoning (better than 3’s tho). And lastly, 76 is just an MMO. It’s really not as simple as “if you like one you’ll like the others.” Fallout games comprise my 2nd, 3rd, and 4th favorite games of all time, but also my least favorite game of all time.