Does macbook Air support attaching external SSDs

Yes.

Any MacBook Air can use external USB / SATA SSDs – although MacBook Airs from model years prior to Mid 2012 will have performance bottlenecked by their slow USB 2.0 ports.

If your MacBook Air is new enough to have USB-C / Thunderbolt ports, you may need a USB-C to USB adapter (or equivalent) to attach external USB / SATA SSDs. But you'll also have additional higher-speed options.

• USB SSDs that run at speeds higher than a USB 3.0 port can support. Typically, Macs with USB-C ports support USB 3.1 Gen 2 speeds ("up to 10 Gbps") on those ports.
• Thunderbolt SSDs that can run at speeds similar to those of internal SSDs. These tend to be the most expensive (due the cost of the Thunderbolt enclosure), and some of them can run a bit hot.

Hey there!

Yes, it does! If you're using an older external SSD with a USB type A connector, you will need a USB-C to USB Adapter - Apple.

-Jack

Yes.