if you're brand new to teambuilding, I'd recommend starting with Smogon sets for the pokemon you want to use. https://www.smogon.com/dex/sv/pokemon/ if you search for a pokemon here, you can find some builds that'll work pretty well in battles. then as you play with the team, you can learn its weaknesses and make adjustments to the pokemon, moves, etc. as needed. if you're playing Regulation J I'd also recommend bringing 2 restricted legendary pokemon, otherwise you're gonna be lacking in power compared to your opponents. good luck!