The basics:
https://www.thesitewizard.com/domain/point-multiple-domains-one-website.shtml
https://www.enom.com/kb/kb/kb_0352-create-301-redirect.htm?Highlight=301
https://www.wikihow.com/Redirect-a-URL
https://www.stepforth.com/blog/2008/redirects-permanent-301-vs-temporary-302/
https://www.hostinger.com/tutorials/adding-a-redirect-for-your-website