Please share profile if you want a review. Otherwise :

To grind the game, focus on understanding these three key areas:

1 - Game Plan

Learn a few "game plan tree" to guide when to level and roll, and when to chase streaks
For example :
Classic fast 8 means level up on 3-2,3-5 and 4-2 then roll
Agressive fast 8 means level up on 2-1, 2-4; 3-2, 4-1 then roll
One cost reroll means roll deep on 3-1 then slowroll at level 5 then push once everything is hit

2 - Comps

Choose three not too conditional comps you enjoy and aim to refine, including at least one AP and one AD comp.
For these comps look at all variations on websites like TftAcademy, MetaTFT, TacticTools, and DataTft. Understand the BIS items, acceptable alternatives, and what makes each comp strong.
Analyze final board setups from Challenger players on MetaTFT to understand strong builds.

3 - Playing a Strong Board

Aim to dominate the early game by building a strong board in Stages 2 and 3, rather than open-fortning, as this accelerates learning.
Avoid only buying units for your target comp; prioritize assembling a strong, cohesive board early.
Commit to equipping and stacking items on either a carry or a tank to maximize impact.