This was my first time shooting high level basketball, and I am not too familiar with how to set everything properly. Tips? Pls be nice lol. I will put un edited shots taken with my 5D Mk 2.

First photo with Red Team #1: 1/8- sec at f/2.8 95mm ISO 125

Second Photo with a clusterf*** of people : 1/80 sec at f/4 92mm ISO 320

It's tough to get pro-level results in this kind of environment. I have seen how it is done in NBA stadiums. They all use a strobe to stop the action. But not a strobe on the camera itself. It is a shared-use strobe built in to the ceiling or upper levels of the stadium. The authorized press photographers get a radio trigger and and the flash lights up the entire court when they take an exposure. it minimizes the distraction to players and fans but gives the stopped-motion they want.
So just a guy at a high-school basketball game? You could try a high-powered strobe either on or off-camera. I imagine one or both coaches might object after the second photo and ask you to stop distracting the players. So that leaves us with using very high-ISO and fast shutter speed in S-priority mode. Basically at 1/8 or 1/80 second you do not have a chance of stopping motion. 1/250s is pretty marginal too. Your goal should be setting for 1/500 or even faster. That means much higher ISO and all the noise that will bring to you. If you camera has an auto-ISO setting, try it. It could salvage some shots. I have a sports mode on my camera bodies, and they do a fair job keeping the shutter speed fast and use the auto-ISO to compensate for when the f-stop bottoms-out. In my Nikons this mode also sets the auto-focus mode to something appropriate for tracking objects moving across the frame.
Beyond that, try shooting RAW mode (or RAW+JPG) and lean on the noise reduction filters of your processing software of choice.
Believe it or not, the rule-of-thirds actually works for subjects in motion pretty well. If you have a runner in the center of the frame, it kind of loses a bit of interest unless you are including action behind and in front of the subject. Put the subject closer to 2/3 of the frame being open in front of it's motion and it looks more right sometimes. Your first shot is more correct with the subject centered, but it can work with shots like the 2nd one where he looks like he is passing the ball.
So that is my 2 cents worth gained from experience multiple years photographing yo-yo contests at a somewhat dimly-lit Mall Of America. ;)