Black screen background, cursor visible and movable, NOTHING WORKS.

I am working on my dad's old MacBook Air (A1465). None of us knew the password, so I used the guest user account. Everything worked fine until I logged out. Now I have this black screen with the cursor. I can move the cursor; I can even do the thing where if I move it around quickly, it gets bigger, but that's it. If any of the qwerty (nonfunction/command) keys are pressed, a quiet clicking sound can barely be heard from the laptop.

I powered it on using an off-brand charger for the first time since about 2017. My dad hasn't used it in years and passed it to my little brother, who certainly did not take good care of it—like everything he owns—and when my family moved to Orlando recently, they dug it out and gave it to me. My goal was to take my dad's old data off of it, wipe it, and put Xubuntu on it.

I have tried every command, trick, and tip I knew or could find online. I have never seen this before, and there is ZERO information anywhere on what this is, what causes it, and how to fix it. I only found ONE comment that sounded close enough on this forum from 2014 that went unanswered. I am at a complete loss.

Before anyone says anything, I have already tried draining the battery. When plugged back in, it skips the reboot altogether and goes right back to this. The power button does not work. Aside from making that faint clicking sound I mentioned earlier, none of the keys work. All I have is the touchpad. It has stayed consistently warm since doing this. The cursor movement is smooth and responsive. At one point, after randomly mashing buttons in frustration, it changed from the pointer to a text cursor (the "I" looking one), but after a second, it went back. It's trying to do something, and it's stuck, I am at a complete loss here.

Specs:

MacOS 10.13 (all I remember seeing)

2 Core i7

8GB DDR3 RAM

128GB SSD (Almost full; only 5.8GB remaining)