I have 1tb of free HDD space, but my Mac keeps offloading files to iCloud. How do I stop that?

System Specs:

16" MacBook Pro - M1 Max - 64Gb memory - 4Tb HDD

WHAT'S HAPPENING:

I splurged on a 4Tb HDD on my MBP so I can always have my files with me. However, my HDD has had 924gb of free space for months despite adding a lot of new content, because it keeps offloading files from my HDD to live on the cloud. I don't like this because I need my files on the go, and the lack of control leads to unwanted surprises. I'm about to go on vacation, and luckily discovered beforehand that NONE of my music is currently on my computer. I'm downloading it back onto my computer now, but again, my hard drive is staying at 924gb of free space, which makes me think it's just offloading more files to the cloud behind my back.

WHAT I WANT:

I want my HDD to fill up, and when it gets close to full, I want to manually decide what files to delete or offload to iCloud (I have 2Tb of iCloud storage). How do I do this? Of note, I sync my desktop and documents folder to iCloud as a backup, but I don't want the Mac to think it's okay to remove that stuff from my computer because of that. I want control.

Any help is greatly appreciated. Thank you!!