All domains hosted (pointing to our IPs) on our servers will automatically get an SSL certificate issued either via Comodo (cPanel Inc) or Let's Encrypt. 99% of the time this works without problems - unless your site actively blocks for the domain validation.
To issue a certificate, it requires that the domain points to our servers and that Comodo or Let's Encrypt can do a so-called "Domain Validation", this process can take up to 15 minutes.
We issue certificates once per 24 hours.
You can also go to cPanel and find the "SSL/TLS Status" page, press "Run AutoSSL", which will try to issue a certificate as well. This process will take up to 15 minutes (or more depending on the number of domains you have).
You can check if you have a valid certificate by going to the website https://ssl-tools.net/webservers and enter your domain, it will take a short while to gather some information. Afterward, you'll be presented with a picture like this:
If you see "Certificates" and "Protocol" as Trustworthy and Secure (both green as above), then you have a valid certificate.