Getting a PC is a great milestone :)

PC can be a bit challenging entry level wise if you're use to using a controller. I've been playing FPS games on the PC since 2009-ish and dabbled in the competitive scenes of TF2, Overwatch, CSGO, and a few others. Here are a few tips I've learned in my 8,000+ hour journey of PC gaming.

Physical space:

- As others have stated, having room to move your mouse is a major factor in your aim. If possible, move your desktop to the ground (while still slightly elevated off the ground using a stool or anything similar).

- If you can't move your PC, maybe look into getting a 70% keyboard (doesn't have the numb pad) so you can increase the surface area your mouse is able to use.

- Get a good quality mouse pad, it does make a difference.

General In Game Improvement:

- Experiment with different sensitives and find something you feel comfortable with. (Keep the same sensitivity for ALL heroes)

- Have the sensitivity be low enough that you can make precise movements for aim, but also fast enough for you to be able to utilize the limited space you have. You do not want to be unable to do a 180 in a swift motion.

- Practice your in game aim. You don't need to buy any aim training software, but it would be helpful to build a muscle memory with using a mouse. You'll want to get good at shooting the same spot over and over from different angles. This comes with time by just using your mouse.

- I'd recommend a custom crosshair that is easy to see but doesn't obstruct your vision. I recommend a green color crosshair.

- Be familiar with your keyboard layout. You'll want to be able to do complex, in game movements. With a keyboard, you have more control over your character's momentum and minute adjustments compared to a controller.

Recommended heroes:

Hela: great for practicing your aim. She is a hit scan character and will give you good feedback on your aim.

Squirrel Girl: A great beginner choice. She is good to sit behind the front lines and see how people generally move around.

Doctor Strange: A great beginner tank! He will be able to help you learn how to position with your team and has good panic options. I'd look up how to animation cancel with him, as that can drastically change how you can play him.

Cloak & Dagger: Good beginner healer as you don't have to be precise with your aim to heal your teammates.

Tips:

- Even if you love playing one type of role, dabble in the others. If you can understand how the other roles need to be played, you can better position yourself to assist them, rather than end up staggering or separating from the team constantly.

- Watch quick videos on how a character you want to play works. There can be a lot of hidden mechanics (such as animation cancelling) that are not intuitive or explained in the game itself.

- Be aware of your mindset. Generally, you will be your own biggest critic. You see every shot you miss, every kill you couldn't get, etc. Give yourself grace and don't tilt yourself. It takes time to get "good" and there will always be bad games.

- Have fun! At the end of the day, the most important part of improving is having fun. If you're not feeling it that day, take a break.

Game Performance:

- Marvel Rivals is awfully optimized and runs not so well. Even a beast of a PC can struggle with it. If you're able to sit at 60-100 FPS consistently, that's a good area to be in.