Not enough space for Sonoma

Y'all. I am so tired. I have a 2019MacbookPro that I basically can no longer use. I couldn't download or use anything I had because they are not capable with my current software (Catalina). I have deleted everything -- and I cannot stress this enough -- *everything* off my Mac except for the apple apps that can't be removed. There is still not enough room to download Sonoma. I don't know what to do anymore, does anyone know a fix for this?