No, there’s no real Star Trek-style tractor beam (yet, anyway). What they’re discussing is parking a large spacecraft near such an asteroid and using its gravity to drag the asteroid onto a course that would miss the Earth. That assumes that we detect the threat early enough to launch such a craft, get it into position, and give it enough time to make sufficient difference to the course. Also, of course, that we have such a spacecraft ready when the threat appears, which so far as I know we don’t at present.
They’re also exploring other possibilities, including other ideas from science-fiction movies. 🙂
In any case, I’m happy to see that we’re taking steps to ensure that what happened to the dinosaurs won’t also happen to us. It’s a remote possibility, but even remote possibilities can happen regularly over a long enough period of time.