Snap Support
The Certbot snap supports the x86_64, ARMv7, and ARMv8 architectures. While we strongly recommend that most users install Certbot through the snap, you can find alternate installation instructions here.
SSH into the serverSSH into the server running your HTTP website as a user with sudo privileges.
Install snapdYou’ll need to install snapd and make sure you follow any instructions to enable classic snap support.
Follow these instructions on snapcraft’s site to install snapd.install snapd
Ensure that your version of snapd is up to dateExecute the following instructions on the command line on the machine to ensure that you have the latest version of snapd.
sudo snap install core; sudo snap refresh core
Remove certbot-auto and any Certbot OS packagesIf you have any Certbot packages installed using an OS package manager like apt, dnf, or yum, you should remove them before installing the Certbot snap to ensure that when you run the command certbot the snap is used rather than the installation from your OS package manager. The exact command to do this depends on your OS, but common examples are sudo apt-get remove certbot, sudo dnf remove certbot, or sudo yum remove certbot.
Install CertbotRun this command on the command line on the machine to install Certbot.
sudo snap install –classic certbot
Prepare the Certbot command
Execute the following instruction on the command line on the machine to ensure that the certbot command can be run.
sudo ln -s /snap/bin/certbot /usr/bin/certbot
Choose how you’d like to run Certbot
Either get and install your certificates…
Run this command to get a certificate and have Certbot edit your apache configuration automatically to serve it, turning on HTTPS access in a single step.
$ sudo certbot --apache
Or, just get a certificate
If you’re feeling more conservative and would like to make the changes to your apache configuration by hand, run this command.
$ sudo certbot certonly –apache
Test automatic renewal
The Certbot packages on your system come with a cron job or systemd timer that will renew your certificates automatically before they expire. You will not need to run Certbot again, unless you change your configuration. You can test automatic renewal for your certificates by running this command:
$ sudo certbot renew --dry-run
he command to renew certbot is installed in one of the following locations:
/etc/crontab//etc/cron.*/*systemctl list-timers
Confirm that Certbot workedTo confirm that your site is set up properly, visit https://yourwebsite.com/ in your browser and look for the lock icon in the URL bar.
source : https://certbot.eff.org/instructions?ws=apache&os=ubuntufocal