Honestly, I really am never sure what to say to a post like this. So I have two words: Quality and Education.
If there are to be pet birds then we need quality birds. By quality, I mean a bird who will make a good pet. That starts with the parents. I mean known quality, not guessing. You can not get known quality from a pet store. You usually need to get that from a breeder. With budgies you are breeding color mutations and to do that properly you need to understand what mutations your birds are, what colors it will produce and the proper pairing of the birds. There are books, and books and books on it. Check a library if you don't want to buy one.
Then you need a breeder who tracks lineage and bands babies. A good breeder should be able to give you a sort of pedigree or lineage for your birds. You need unrelated birds or at least birds who not closely related. You mentioned, that you know your birds are unrelated, how? Parents need to be healthy and well tempered as pets. Quality housing, nestbox, food, if you are handfeeding you need the right equipment too. Quality in Quality out.
Education. Education for you, lots and lots of it. Books and real sources, not internet hearsay. Mentors and excellent breeders. Learn everything that you can about birds. Not just budgies, parrots of all kinds. Outdoor birds. Everything feeds the passion and can potentially help you.
Learn about training and weaning and socializing. What makes a good pet bird? What does an ideal environment look like?
Volunteer or mentor with someone. It can be hard to find someone but that doesn't mean you can not try. We had a good local bird shop nearby and they answered questions and let me watch them feed babies. Offer to clean cages or something in exchange for the privilege.
Finally, it is a breeders responsibility to educate the people who they sell the babies too. You can not control what they do when the babies leave but you can make sure that they know what they should be doing.
I started out with pet budgies (not breeding) when I was a little girl and as a teenager I dreamed that one day I would breed birds because I love birds and I was passionate about them. I did raise parrotlets for several years. I was grown, had my own home and I borrowed money to get started. I took it seriously. Tracked down unrelated birds and made pairs properly. I was mentored. I did research for years. Over a year before I got my birds and then continuously thereafter. It turned out to be great fun and very satisfying but had it's share of heartbreak as well.
Sadly, it is almost impossible to find good breeding stock for parrotlets anymore, they are all but lost to poor breeding practices. The bloodlines are muddy, the color lines are polluted. Parrotlets these days are up to 25% smaller and live about half as long. This is because of in discriminant breeding and it is so, so sad.
This may be over your head and it may sound like a lot but if you think about and ask the questions and educate yourself then you may well be part of the solution that will promote better quality pets and better quality care. If you care enough to do the work and be patient and set yourself and your birds up for success then you can expect to learn something and enrich the lives of others and of the birds in your care.
If you are not careful, cautious and thorough then you can expect heartache for you and the birds.
I am all for the former but have seen too much of the later.
Stick around here for a while and read, read, read. You'll learn a lot and it will broaden your perspective which is a great thing for a young person who is eager to learn