Is it possible to upgrade my MacBook Air 2017 storage ?

Other World Computing sells internal SSD upgrade kits for Mid 2017 MacBook Airs.

https://eshop.macsales.com/shop/ssd/owc/macbook-air/2013-2014-2015

OWC says you need to upgrade to High Sierra or higher before installing them. That's true, but I don't believe that it's the complete story.

2017 MacBook Airs can run Monterey. If you ever plan on running it, you should install it before installing any third-party internal SSD. I don't believe you have to install it on the internal drive, but you must install it somewhere.

Why? If I remember other threads correctly, the Monterey installer checks to see if it needs to upgrade your Mac's firmware. If it thinks the firmware needs updating, and the update code detects that your Mac's internal SSD is not an Apple SSD, the firmware update will fail, and the Monterey upgrade will fail along with it.

Once you've done a successful installation of Monterey and the firmware is upgraded, I believe that you can install a non-Apple SSD and then successfully install Monterey on it.

That is not memory, that is your drive/storage and no, it cannot be upgraded - sorry.

Have a look at this web site. It depends upon if you are up to it and which exact model MBA you have.

https://everymac.com/systems/apple/macbook-air/specs/macbook-air-core-i5-1.8-13-2017-specs.html#macspecs4

Okay, yes it isn't "memory" in the strict sense. But the OP strongly implies they want a larger drive, that's what's important here. According to Everymac that is possible on some 2017 MBAs, though it surprises me.