Easiest wayto learn an MacBook Air

macOS User Guide - Apple Support

I suggest starting with the following articles:

• Mac Basics - Apple
• Meet your Mac - Apple Support
• macOS User Guide - Apple Support
• Use trackpad and mouse gestures on Mac - Apple Support

Further, you can try these resources, as well:

• Your local Apple Store periodically offers short "get acquainted with your Mac" sessions. Just contact your store to find out when they may be offering these at that location. They typically offer both group or one-on-one sessions.
• The book store (in-person or online). There are numerous books/articles on learning how to use a Mac to choose from.
• Ask a friend or relative, who have Macs, to help you out.
• The Internet.