G5 15 5500, poor gaming performance, GPU maxed

So I’m running a Dell G5 laptop, it’s pretty new. It has a RTX 2060, i7-10750H, 16 GB RAM and a decent SSD. My GPU drivers are up to date. I updated the BIOS. I basically updated every driver I can imagine. I made sure to set the 2060 as the default card for all programs in NVIDIA Control Panel.

I booted up Halo Infinite last night and had to bump settings down to low and was still only getting 10-15 FPS at 1080P. Forza Horizon 5 actually optimized itself to high settings and it was running fine throughout the intro, then suddenly dropped to 15-20 FPS. I switched to low settings and it was still in that FPS range, no difference. Forza’s GPU tracker said I was hitting 98-100% capacity on the GPU, even when at a complete standstill in the game and with no other NPCs or large objects around.

Something else that happens occasionally is I'll boot into a Halo match, get a steady 60 FPS for a few minutes, then it'll suddenly drop to and hover around 10-20 FPS again. Almost seems like the laptop is heating up and throttling itself because of it or something. I changed my fan settings in Dell Power Manager to full performance already but that didn't help.

Most importantly though, I tried both of these games on my fiance's Lenovo laptop that has the exact same specs and they ran totally fine at medium-high settings. This makes it pretty clear there's an issue with my G5 5500.

Any idea what’s going on?
If you need any other info from me to help, please let me know!