Parakeet! The only birds I've kept... during my childhood.
The first pair died for unknown reasons. Maybe food poisoning. There could be pesticide on the vegetable I gave them as treat.
The second pair someone broke the cage and got away.
The third pair... had one more addition when one parakeet probably escaped from someone else's home and entered mine lol. I had these 3 for a very long time, until my dad gave them away because he thought I spent too much time on them and not enough on study! Lame! That was two decades ago.
You definitely need two. Or they will get lonely.
They don't exactly require large cages, but if you show me the link to the cage, I might be able to tell you more.