Jag har glömt lösenord på min Mac

Translated by google:

>>Hi

I forgot my password on my Mac. Tried all the ways but it didn't work <<

A Mac login password can at least be reset, have a look at the related article:

If you forgot your Mac login password - Apple Support

Om ** har glömt inloggningslösenordet till din Mac - Apple-support (SE)

If this does not work, erasing the Mac and restoring it from the scratch would the the ultimate thing to do.