What type of cable do I need to connect a macbook air 2015 to new (2020/m1) macbook air in target disk mode?

I have a 2015 macbook air that is stuck in the reboot (out of space) loop while trying to upgrade to Big Sur. I would like to boot it in target disk mode so I can access it from a new M1 Macbook Air. I have been unable to find out what type of cable I need to do this (assuming it is even possible to mount the High Sierra disk from Big Sur). Can I do it with an adapter on the m1 MBA and a USB-A to USB-A cable? If not, what would I need to connect to the thunderbolt port on the 2015 MBA?