These are ProRes 4444 QuickTime files with a transparent background (alpha channel).
Drop one on the track above your footage and the logo fades in over your shot.
Premiere, Final Cut, DaVinci Resolve and CapCut (desktop) all read the alpha automatically.
If your editor shows a black background instead, look for an "alpha" or "straight/premultiplied" setting on the clip.
The logo is the gradient version with white "spot", so use it over dark or mid-tone footage. Over bright footage, add a dark scrim first or use the all-white logo from 01-logos.
