Yes, of course. Most people wouldn't summon them if they couldn't.

{He laughs a bit at your questions.}
Most people play with holograms, but you can also just play on a table. I didn't even start playing with holograms until a few years ago.
The rules say that a deck must be between 40 and 60 cards. Most people try to stick closer to 40.
And yes, I have my deck and duel disk with me, but no one else plays here since Nii-san left, so...