how to factory reset Apple Mac

hi everyone,

I received a laptop for my daughter to do home schooling. unfortunately I can only use the guess setting as I don't have the admin name or password.

I have researched online and it has sed to hold the command key and 4 to do it or even reset the computer and do the same commands. which is not working.

I really need to download zoom for her lessons

HELPPPP. and yes I have thought about asking the giver but I have no way of contacting her