Any tips/suggestions to improve?

Let's see this game you played:

1. 5.e5? blocks your bishop road.
2. 6.exf6? Nxf6 and Black's Knight becomes an active piece.
3. 9.c3? Here 9.Be2 followed by 10.O-O looks better to ensure your King's position.
4. 10.c4? Again 9.Be2 and 10.O-O seems better. Even 10.Nc4, attacking the Queen, is good.
5. 12.Ne4? The idea is correct but 12.Ng5 followed by 13.Nge4 is better yet. After 12.Ne4, Black can create a passed pawn on "d" file, capturing on e4.
6. 13.Qd2? The pawn on c5 is unprotected now. You missed 13.Nxc5.
7. 14.O-O? Castling is normally a good move. But here you missed 14.Nxd4 (discovered attack).
8. 17.Qg5? Exchanging the Queens is not the best because White is down a pawn. For example, you might pressing along the semi-open file "e", in front of the backward e6-pawn.
9. 24...Nc2? and you resigned! Why? After 25.Bxc2 Bxe4 26.Rxe4 dxc2 27.Rc1 White recovers the pawn.

How to Reassess Your Chess and My System are rotten materials.

@kingsindianpatzer What do you mean rotten materials? What's your recommendation for "unrotten / better" materials?

You'd learn more about chess from a book on backgammon than you would from those books.

Interesting how many masters would disagree with you. @billy_ombima there's nothing wrong with those books. @kingsindianpatzer is definitely in the minority there.

@ioxod Ever heard of the learning pyramid? You learn more by actually doing than just reading books. My advice: Join company of other chess players who are better than you, visit a local chess club. Solve a lot of puzzles like Mate in 1, Mate in 2, Mate in 3, learn how to checkmate etc... step by step. You also start a marathon with the first step, so it's the same in chess. Do a little on a daily basis.

@jeffforever never heard of the learning pyramid, but it makes sense. thank you for the advice

Let them disagree. Most chess masters are horrible teachers that don't know how they got good in the first place.

Noted

hehe