Help! Constant FPS drop and disconnecting from game!

So I don't know if anyone has had this problem before, but ONLY when I play League, I constantly drop FPS(?) or disconnect from the game. My wifi connection is spot on and I usually get 50 ping. My ping will never change from 50 that's just usually how it is. Some games for me go super smoothly without this problem, but others I drop FPS constantly. And I do not know if I can even call it an FPS drop. Like my character keeps moving every time I click and I can use my moves freely, but other characters in the game will walk towards me but the characters feet isn't moving so he is just like gliding towards my character. And then suddenly, my game just comes back to reality and I spawn back in normal time and I die. So to my teammates it looks like I'm walking into them and just inting or I'm just walking around and not helping during a team fight. I'm a typical girl and i don't know the specs of my laptop or anything, but the laptop I own is "OMEN Laptop - 15t Gaming" or something like that. And keep in mind, this only happens when I play League. No other game.