Dear PhylumChess, Upon looking into your profile and watching some of your chess game, I pleased to know that you basic chess understanding of the opening with with pieces but you do not like to play with black pieces.
It looks like that two different players are playing with this account, with white pieces you play much better and with black pieces you dont play well.
One reason may be that you dont like to play with black pieces or you dont know proper defenses. please clear this in reply.
Before going to analysis let’s watch one of your chess game with white’s pieces.
Opening Suggestions
As I mentioned above that you have basic knowledge of chess opening, like controling the center, developing pieces, and castling but having basic knowledge will not improve you much, you need to have opening repertoire.
Now days getting opening repertoire is very easy, just go Youtube and searching opening repertoire with white pieces and black pieces and you will get some lessons, wacth them carefuly, understand its ideas and you are ready to go.
I think you should learn London System opening, which has clear ideas and setup is easy to master.
Middlegame Suggestion
In the middlegame, you should attack your opponent’s weakness, in some of your game you exploited well, but in some of your chess games you blunder your pieces and even a queen.
In order to avoid blunders you must look out for hanging piece before moving your next piece.
Endgame Suggestion
You are not reaching to the endgame, either you are wining in the middlegame or losing, anyway my suggestion is that you should learn basic rook endgame which will help you a lot.
Conclusion
Learn or create your opening repertoire, look for weakness in the middlegame, and learn endgame especially rook endgame.

If you still have any questions, feel free to ask.