Changed password and forgot it: how to reset with Mojave?

I wanted to give away my hackintosh and changed the password to sth I don’t remember (yeah I know)

How do I reset it and keep all my data? Do I have to make a recovery usb stick? And would it have to be the exact same Mojave version or doesn’t it matter as long as it’s 10.14? There isn’t an option for booting the recovery partition in clover as I might have hid it before.

Thanks guys, I screwed up and desperately need help.