Remove DEP notification MacBook

I've just bought my first MacBook and I found out that it is enrolled in MDM/DEP. The guy I bought it from had it completely sealed up with original packaging so I never thought it would have problems with it, while I also paid almost retail price. Anyway, I have tried different solutions posted here to remove DEP notification and I get stuck at moving files to /etc/hosts. ZSH give back "access decided" error or mounting with root returns "mount_apfs: volume could not be mounted: Permission denied mount: / failed with 66". How can I gain access to /etc/hosts ? I have searched everywhere and for M1 Macs I couldn't find an answer. Thank you!