Moving from a subdomain with a parked domain name

I want to move my WordPress website from a sub-domain i.e.

mysubdomain.mainwebsitename.co.uk

to its own co.uk domain, the sub-domain currently has a parked co.uk domain name and I want to move the whole site over to a hosting space for that co.uk domain.

Is it possible to use Better Search Replace to do this and if it can be done can you tell me please, how can it be managed.

I am not a particularly techy person and am not sure if this is even possible, so would appreciate your advice with this.

Many thanks

https://www.ads-software.com/plugins/better-search-replace/