Can't enable Admin. account

I am trying to enable the administrator account in Windows 10 Pro but without much luck.

Whatever option I try I am left with a request asking me for an 'admin username and password', which I don't have, but the only active box available is for 'No' anyway.

If I use the 'command prompt' route then I am not offered the same options that are indicated by the guide I am referring to.

Tried the Administrator tab in 'Local Users and Groups', where the Admin. account is ticked disabled but it won't let enable it.

It seems I am blocked at every point from enabling this and I can't carry out certain actions on the PC until it is.

I will be eternally grateful if there is someone who can shine some light on this. I am obviously doing something wrong but I don't know what.

Thanks

Welcome to the forum. Are you signed in with an admin account why don't you know the admin password?

Thanks,

I'm signed in with my Microsoft account and to my knowledge I never created an Admin. password. Each time I go to the UAC I am told I need an admin. 'username and password to continue' but the only option available is 'No'.