I can't install SSL certificate on temporary Bluehost domain / Unable to install SSL certificate on Bluehost

SSL certificates can only be installed on your own domain, not a temporary Bluehost domain (e.g. box5568.temp.domains/~sslzen). Replace the temporary domain with your real one first — see Bluehost's guide: https://www.bluehost.com/help/article/using-your-temporary-url-with-wordpress#changing-from-temp (video: https://www.youtube.com/watch?v=E2I_8C5vMf4).