I just made an account yesterday and I can't figure out how to add pets that I have made to my stables. Can someone help me?

TIA!!

If by 'make' you mean 'designed in the generator', you need to have an Essence (< guide to essences) in order to do that (the guide should cover just about everything- ways to get essences, how to use them, the differences between the three types of essence etc.- if you have any questions on the matter that it doesn't cover you can either ask us here or PM us)

Egglings that you get via breeding or find while exploring start in the hatchery (note that you won't be able to breed Ember for about 17 more days, as Starter pets count as generated pets, and begin life at the start of adolescence, rather than adulthood)

Tamed pets that you catch automatically go to the stables (though note that they can flee from a battle when you try to catch them, so make sure to check the battle log)

(Not related to the question, but since your unnamed nixi boy is on your party, you'll want to assign his element and proficiency point. I'd suggest looking at this guide, as well as give him equips that fit with the element and party position you give him)

Thank you!