So I received a bonsai starter kit as a birthday gift and decided to give it a shot. I know that starter kits are not the best option but I've always loved bonsai trees and I figured, at the least, I could just treat these as my introduction into the world of miniature trees.

So far, I have only planted my 5 Pinus Aristata seeds. I have planted them in the rather small, but deep, plastic pot that my kit came with. Since then, I have purchased a set of 6 inch "trainer trays/pots" for the future. I've red that planting the seeds, spaced out together in the same pot, is a common way for seed starting bonsai trees. I am just unsure of when to move these 5 seedlings out of their initial small pot, as they are already about 2 inches tall and rather close together.
And for the 3 other sets of seeds, I'm wondering if I should skip the pots that came with the kit all together. Should I start them in the shallow, wider training trays? Should I only keep a certain amount together?

I'm not looking for tutorials or detailed explanations but I would greatly appreciate some beginner tips for seed starting. I don't have much hope for these but I would still like to learn and try my best. It would be nice to see at least 1 of them survive and grow into a beautiful bonsai.

Additional Info:
If you're curious, in this kit I received multiple seeds for 4 different kinds of trees:
1. Pinus Aristata
2. Picea Abies
3. Jacaranda Mimosifolia
4. Delonix Regia
I live in Arizona, where it's pretty much hot year round. So I have the Pinus Aristata seeds indoors right now but after doing some research I found that these are more of an outdoors bonsai tree.

You do not start bonsai from seed you grow trees. All species of trees are outdoor species and will not survive inside. Read the how to on this site.

As m5.. says: outside. There is no such thing as an indoor tree ( not one tree in the entire world lives naturally indoors).

Treat your seedlings like you would treat every other seedling: let them grow and repot when needed. They are 10-15 years away from being a pre-bonsai so the first decade or so there is nothing more to do then purely horticultural. Shallow pots, bonsai soil, bonsai fertiliser, .. all a waste of money. Good potting soil, a container ( or better into the ground), and general fertiliser are all they need.

If ( and most beginners are) you are eager to someting "bonsai-ish" look around in nurseries for junipers, mugo pines, ...that you can find in abundance there. Look for a twisted trunk, some good branches, . Start your bonsai journey from there. By the time you will have some knowledge your seedlings will be old enough to do some real work on.
Do bear in mind that turning a tree into a bonsai takes time ( decades), and the use of numerous techniques on specific moments in the year, depending on a lot of variables...

In addition to nurseries, look around neighbor's yards. If somebody is relandscaping they might be willing to let you dig up an old shrub or two. I have more azaleas than anybody needs right now, a boxwood, and some others.

Another idea is layering an existing tree. You get something with a thick trunk pretty fast.

Whatever you do, remember that the biggest thing you need for bonsai is patience.

beginner here, but i would think that saying "all species of trees....will not survive inside" is a bit of hyperbole. I think most everyone can point to houseplants of our own that are trees growing indoors just fine.

Many so called house plants are species that grow in rain forest or in shady low light conditions and are able to survive in the poor conditions in a house. There is a big difference to those and the trees that grow in temperate or colder regions that need seasons including cold in the winter and also a much higher level of light at any time. There may be a few species that do survive inside but that does not mean they grow well or that they would not be much better in the natural environment. Time after time in this forum we have people saying they have a Juniper that has died and every time the plant has been inside which has killed it.

i was more referring to baobabs, ficus, and such that are commonly kept indoors. i didnt even know people kept junipers inside lol. didnt think that was a thing.

thanks for the information!

Just gonna throw this link here: bonsaitonight.com/how-to-grow-bonsai-from-seed-or-cutting/