Password dont work to log on

Hello, I am new to linux systems in general. I had a friend put PureOS on my lenovo laptop, and when I got it back I changed the password. The next day , my new password did not let me in. And he said he didn’t make a root user, it just said Home when I went to log in. I can not figure out how to get into my computer now to reset my password because mine don’t work anymore. I know I put it in right but also, I do not know how to tell if he really did make a root and just didn’t tell me. Someone please help so I can use my laptop again!

Well unfortunately there is not a “reset” password feature. I would try the password he gave you initially and then try variations of what you think the password you changed it to. Maybe you fat fingered it (hit a near by key to the key you meant to type), I have done that, twice the same way and locked my self out before.
There is probably not a password for “root”, depending on how he set it up. He probably just gave your user administrator rights.
Passwords are case sensitive, just in case you might have not capitalized when you should have.
You may need to do a reinstall if you cannot figure out the password.
Good luck

You should be able to use single user mode to reset the password. PureOS is based on Debian so any guide for Debian, Ubuntu, Mint, etc should work for you.