Total newbie questions

• I usually play with mouse and keyboard. I understand that I won't be able to see them with the glasses on, will I? So what kind of devices will I have to control movement and actions?

That depends. Some games are played natively (installed on the headset) and you use the Touch controllers to play them. They are great and have motion control, touch recognition and haptic feedback. Other games can be played remotely off the PC (PCVR games) from various game libraries such as Steam, Meta Horizon Link, VivePort, etc. Many of these games can be played using the Touch controllers, or gamepads, or mouse and keyboard. Usually you can't see your mouse and keyboard, but you can peek at them through the gap at the bottom of the headset or briefly switch on the passthrough camera to see them.

• To walk or run in a game will have I to actually walk or run? Would I need some extra physical room to play with RV glasses? Is not very easy to hit some item like a can of beer and throw it accidentally down to the floor?

Not necessarily. You can physically move around if you have a large playspace, but you can play seated in most games, and you can also move around virtually by moving your control sticks or by "teleporting". To prevent accidents, the headset sets up a virtual boundary space by mapping out all the obstacles in your room. You get intuitive alerts when you get too close to the boundaries. You still have to take some level of care though.

I'm partially sight-impaired.

I am short sighted in one eye, long sighted in the other, and have astigmatism. But I can see quite clearly in my Quest 3 without needing to wear my glasses. The best thing to do would be for you to ask for a demo of the Quest 3 at your local store, and see how well it works for you. The other thing to be aware of is that VR can cause severe motion sickness for some people. The headset and games have various options to help reduce motion sickness (e.g. teleporting instead of gliding, also vignetting the image while turning etc). I'm lucky, I never get any vertigo at all.

So try before you buy. Hope that helps.