You can affect you the easiest.
The easiest way to achieve success at anything is: only work on the things that you can affect.
If you take responsibility for your success, you have a chance.
The opposite of responsibility is: BLAME.
If you blame others, the end result is, no change in circumstances.
If you take responsibility for what you say, what you learn, how you act, and what you expose yourself to, then have the best chance for self-success.
This simple truth will get you further than any other: I am responsible for me.
If you will focus 90% (or more) of your effort on the things you can affect – on the things you can make better, on the people you can influence, on the things you can change – then “all of a sudden” you will start to improve – AND THEN things will improve.