How crazy is the IAH airport?

Not sure if this is the right place to ask this but figured it was my best bet. I'm flying alone for the first time and I've never been to the George Bush airport so I have no idea what to expect out of it. The airport in my city only has 4 gates so I know I'm in for a huge difference but I'm not sure what exactly to do. I'm flying domestic and checking 1 bag (already paid and checking in on my app) but still not sure how early to get to the airport. Is an hour enough or should I go earlier?

Any frequent travelers have any tips to get me through this smoothly? Thanks in advance!

Edit: my flight is with United airlines and is early afternoon if that changes anything about crowding or location.