To be honest everyone’s talking about using Dino gateways to capture dinos but I never have used them. What I use is 10 pillars making a sort of u same and then stacking the rest on. I then add a ceiling to the middle pillar. I get a Argentavis to chase me and I run through the structure. Once the Argentavis is in structure, I place a stone fence behind it trapping it. I’ve done this method on a multitude of levels ranging from the basic 15 to 450.
To tame one easy all you have to do is kill something so the argent Avis can eat, and while it’s healing you must knock it out with tranq arrows or darts. If it is knocked out while healing it’ll starve immediately and it’ll tame in seconds no matter what level!
A common trap for Arial creatures in general is that you craft about 4 stone dino gateways, then place them in front of each other (so that it's just a straight row of gateways). The ones on the outside place a little farther away so that you can walk through the sides, then have gates on the outer gatways having one of them open so that the bird can fly in, once you find the bird of choice, kite it into the trap, go through the side space that is larger on the end, and quickly go round to the open gate to close it and now you have easy tame stuck inside your trap. (You can modify this if you want, particularly the size of the gateways for the bigger creatures and it can be used for terrestrial creatures too if you want)
I keep seeing people saying you need a bunch of stuff, but here’s how I did it as a level 56 single player in only hide armor.
Get a flying mount and find an argy (theyre in the snow and tall mountains) , then get close to one (just out of the Agro zone). If you get too close and it chases you, don’t worry, it won’t chase too far! Now that you’re near it, smack it. Just with anything you have. Charge it and smack it. Now that it’s angry shoot it while moving backwards… it doesn’t do much damage as long as it’s below level 40 (on mobile)… that’s basically it! It’ll tame with raw meat (the ratio of food per level is around 1:2) it’ll only take 10-15 tranq arrows, and you only need one narcotic! That’s all!