I just want to post but for some reason people keep targetting the criticism on these specific things.
You can get the Judge Function by talking to the Pokémon Centre nurse after defeating every base game story path. Then, go into the summary screen of a Pokémon and go to the moves and stats page. Click the L button and it'll bring up your Pokémon's EVs. Unfortunately, it is impossible to view exact EV's in-game. You can only tell if an EV is maxed out, as the stat will sparkle while using the judge function.
It is possible to figure out a Pokémon's EV's by using a stat calculator, but this requires knowledge of a Pokemon's IVs which are also not viewable in game. If you're training a Pokémon for competitive, you could use bottle caps to max out a Pokémon's IV's. You'll then know it's IVs are 31 and be able to determine the EV's based on that.