CDN is quickest way to get started, include this snippet on header of your HTML file and start using without hosting icon files on your server!
<link rel="stylesheet" href="https://cdn.lineicons.com/4.0/lineicons.css" />
If you purchased Lineicons Pro, you will be able to use Pro icons with your site by listing it on your account. To obtain your CDN link please login to your account and follow these steps ...
CDN Settings-> Add Site-> Copy/Paste CDN URL on Your Site-> Start Using!
CDN limit is linked with subscription type, you can always add/remove sites depending on your needs.