same way as in eclipse. if you're new to mod dev i suggest learning the basics like adding custom blocks in the game.
plus people would be here forever trying to teach you its honestly why https://www.google.com/ is the best since there is already heaps of guides on potions and particles(outdated but updated easily).
idk if thats gonna help you if not then idk learn java?
p.s this should help to
oh and this