Installing let's Encrypt

Certbot, Let's encrypt provides free SSL certificate head to their site where you can select your operation system and it will show you what software you need to install. Once you have installed certbot to install ssl certificate on a single domain this is wah tou need to do:

sudo certbot certonly --cert-name domain-name.com -d domain-name.com

After that depending how you want your domain name to be accessed e.g. without www https://example.com then you would need to add this to your .htaccess file.

RewriteEngine On
RewriteBase /
RewriteCond %{HTTP_HOST} ^www\.(.*)$ [NC]
RewriteRule ^(.*)$ http://%1/$1 [R=301,L]

Removing Let's Encrypt Certificate

If you want to remove let's encrypt certificate one of the things you would want to do is list all the domain which have ssl, you can do that as follows:

certbot certificates

and delete to delete you need to do the following:

certbot delete --cert-name example.com