I’m confused on the difference between thunderbolt and type c. I think they both are physically similar but the thunderbolt can handle faster speeds? I’ve just upgraded to a new 15" MacBook Air and want a secondary flash drive for old files that aren’t regularly used as I had on my old 2015 air where I used a a micro sd drive in a sd adapter which worked great. I guess I want to know if a USB type C flash drive would do the job?

Would anybody be able to steer me to something that would work? Thanks!