Since it doesn’t seem like your operating system has a packaged version of Certbot, you should use our certbot-auto script to get a copy:
wget https://dl.eff.org/certbot-auto chmod a+x certbot-auto
certbot-auto accepts the same flags as certbot; it installs all of its own dependencies and updates the client code automatically.
Certbot’s DNS plugins which can be used to automate obtaining a wildcard certificate from Let’s Encrypt’s ACMEv2 server are not available for your OS yet. This should change soon but if you don’t want to wait, you can use these plugins now by running Certbot in Docker instead of using the instructions on this page.
Improving your website security through encryption, even on the most basic servers, can increase your visitors’ trust in your site and your ability to run it. Setting up encryption on your web host has generally been complicated and expensive, which often deters administrators whose web applications might not depend on user input. Let’s Encrypt aims to change this by making implementing encryption on any website easier. They are an open and free project that allows obtaining and installing of certificates through simple, automated, commands.