Migration from W10P to Ubuntu

[3Dscrewer]

Hi, I’m wondering if it is possible to migrate the data from W10P to Ubuntu.
Since my “Server” was 24/7 it needs up to 2 kw/h per day.
So I bought a Synology 920+ and run it in an Ubuntu VM, no more over night.

So I have a couple of users and I don’t know the credentials. It would be nice to keep them.
Also I don’t know how to extract the PW at the old system, name and email I can read of course.

Any suggestions?
TIA