I have a Digital Ocean Droplet and changed A-Records for 5 domains to point to the server. I would like to install SSL (lets encrypt) for all 5 domains. Is this possible?
I run this setup to backend identify the domain name and using this change the language.
Yes, it is.
It depends on what challenge you're going to use.
If you're using the certbot (which I can recommend!) you can simply append multiple domains with -d
For example (you can even use wildcards):
certbot -d domain1.tld,domain2.tld,domain3.tld,*.domain3.tld
There is some good documentation on DigitalOcean itself
Otherwise check out the website or the official docs.