how do you get better in games

Best thing you can do for a given game is think about why you might have failed in any given situation.
When you're back to the lobby, win or lose, take a second to think about any standout moments in your play, be they kills or deaths, objective captures, or losses.

You need to understand how people and AI are getting the upper hand on you, did you check your corners, did you keep an eye on your radar, did you choose the right tool for the job, did you rush to accomplish something small instead of looking at if it was necessary?

Always gotta be mindful of what you're not doing, and what you're relying on too heavily that leaves you vulnerable to people spotting patterns.