Where the game is played shouldn't make a difference in how you play but what you are playing for and who you are playing against might.
The biggest difference you are going to find between online and live tournaments is going to be the structure. Yes there is exceptions to every rule but for the most part you are going to find a better structure for your money online. This will affect how you play live because you won't get to see as many
hands and if its a really poor structure you will find yourself in shove spots a lot faster than you would online.
Also guaranteed money vs your buy in will be dramatically different online. You can find a $10-20k tournament for $20-50 online but live...you might have to travel a bit to even find a $20k GTD and even then its going to cost you a couple maybe three hundred to get in.
All that being said what you lose out on between those two things playing live depending on the game and where it is usually you can make up for that lost edge by taking advantage of the poorness of the player pool. Live players are mostly in part worse than online players.
I personally try to take the best of both worlds, I am about an hour away from a casino that holds a $75 $10k I think twice a month. And a $120 $20k at least once a week. Those are good games when playing live, this casino has a little better playing pool than most but it is still a really great value game.
Hope this helps, sorry for the ramble.