There is no single correct way to achieve this. The work to do this lies outside of WordPress itself. The general process requires the following steps. Point the new domains/subdomains to your WordPress site. I’d recommend using A records as CNAMES have gotchas for new players. Never use a CNAME on example.com (but you can … Read more
Change Domain Name
Site is not fully working after migration
How to redirect URL to a subdomain except one folder that needs to go somewhere else
Why are my external links / domain authority dropping after switching hosting services? [closed]
Can I have a web application run along my WordPress hosted website?
Place a website on WordPress on a subdomain
I’ve mistakenly installed another wordpress in my main domain instead of subdomain
Image URLs in the post content aren’t affected by the “WordPress Address” and “Site Address” settings. They’re part of the text of the post, rather than something that’s generated using those settings. If you’ve moved to a new domain, you’ll need to change these URLs. If you’re comfortable using the command line, I recommend installing … Read more
How to Setup 2 Domains on a Single WordPress (Regions Filter)?