I’m trying to find new openings/gambits to level up my elo rating anyone have ideas?
At a rating of 400, you don't need any "trick" openings or gambits. You need to stick to the basic principles of control the center, knights before bishops, castle early, and don't hang pieces. Openings come a lot later.
Opening study is terribly over-rated.
You would get more benefit (and more rating) out of almost any other form of study.
Endgames, for example. Nobody at your rating level can play endgames properly.
And I do NOT mean "How to checkmate with King and Rook" or something silly like that. Chimpanzees can do that. I mean "How to win a King-and-Pawn endgame (or a Rook-and-Pawn endgame) if you have an extra Pawn". Or how to draw an endgame when you are a Pawn down.
A knowledge of endgame play will bring you HUNDREDS of wins, at your level.
AND it will improve your overall level of play.