GURPS Lite is available for free, and includes the basic rules on how to do things, combat, etc. It doesn't include the introductory "What is a GM?" stuff to save space; though that does show up in the Basic Set. You can extrapolate quite a lot from just what's in Lite - a lot of the stuff in even the Basic Set that's not in Lite is corner cases (how far can I jump? What can I shift or drag, instead of lifting?), clarifications (how long does it take me to dig a hole?)... and lots more skills and abilities!

Mook has some very basic combat examples worked through here

In a little different vein, Feral Sword Wielding Wizard has some fight scenes from movies he's gone through and labeled with GURPS combat maneuvers, so you can see how they work! (Just keep in mind this is with a bunch of optional rules!)

So much

https://www.sjgames.com/gurps/books/

If you like Actual Play shows, the Film Reroll podcast plays exclusively in GURPS. They play a fairly light version of the rules, but still make custom mechanics for various settings that show how modular of a system it is.

The show takes the premise of a movie and plays it out as a roleplay campaign. My favorite is Friday the 13th: The Final Chapter, in which the GM tells the players they're playing an obscure teen romance from the 80s so that they wouldn't know they were in a horror movie. I probably wouldn't recommend that for a table, but the actors know to expect tricks and it works very well as entertainment.