How do I renew a letsencrypt SSL certificate on fresh linux box using certbot?

No, it’s no different than a “renew”.

Essentially all the “renew” command does is generate new certificates for you, so there is no difference. It’s just an easier way to automate things when you have several different domains that the “renew” flag will use the existing data of domain names etc to generate new certificates (if you have all that info stored, which you don’t on this server )