Welcome Avi!
Live poker is a different game from online, so it's natural to feel that you're not as strong when playing live. It's like learning how to play a new variation of poker - you'll need to practice and work on those things you should do in live games, like waiting till your opponents have looked at their cards before you look at yours (a lot of people give things away about the strength of their hand when they see their cards) and always putting a chip or other protector on your cards until the action comes to you, even if you plan on folding. Experienced players will notice if you only protect the good hands. You want to make sure you always do the same thing, no matter your cards.
As for the comfort factor, well...that's all up to the game host! Most casinos have very comfortable chairs though, since they're interested in keeping you there as long as possible.
In time, you'll have all the different aspects down well enough that you can be having a great time with your friends and also be the most observent player at the table. Online poker is quite profitable, but there is something about actually feeling the cards and chips in your hands that makes live poker such a rewarding experience.