I’ve done my fair share of flying with kids, and each time, it’s a little different. I won’t say it gets easier, because you never know what kind of mood they are going to be in. But you become more prepared and more inclined to deal with the meltdowns, tantrums, or just plain boredom.
The first time I ever flew with Nolan, he was 3 months old. So it was easy peasy. I nursed him on takeoff and he slept until landing, where I nursed him again. As they get older, it gets a little trickier because 1) they are more aware of their surroundings 2) they become mobile and have NO desire to sit still.