Best and simplest for beginners as well as World Championship candidates is to defend 1 e4 e5 and 1 d4 d5 as black and to open 1 e4 as white.
Good openings for new players

You should prepare your repertoire according to your own chess tastes and style. It is very important that you should like and understand the typical positions which result from your chosen opening. One good method consists of choosing, as a model, a strong player who plays your choice of opening particularly well and often, and then following his games. You study some model games in order, above all, to get a better understanding of the middlegame.
What is the best opening for beginners that you know? And what advantage does it gives when played? 🤔