Is it possible to charge my MacBook Air 15" M2 by normal usb cable/port?

See the following from Charge the MacBook Air battery - Apple Support

To charge the battery on MacBook Air with M2 chip, use the MagSafe 3 port with the USB-C to MagSafe 3 Cable connected to the power adapter, or one of the Thunderbolt ports with a USB-C Charge Cable connected to the power adapter.

Hey there!

Yes, you can charge that way! I charge my MacBook Air 13-inch using that method when it's at my desk and connected to an OWC Thunderbolt Dock.

-Jack