Right now I have all of my seedlings in just regular organic soil made by baccto I just came across some bonsai soil and picked it up. I’ve never used this before and I’m curious, if I replant one of my seedlings into this, do I need to mix some organic soil in there too? Are my seedlings ready for this type of soil?

Well first of all you should tell us what the age of the seedlings; then the species, and after that the location of them.
I wouldn't repot, slip pot, or up pot a seedling that's doing well and is not root bound.
But if you must repot it, the answer is...
It depends.
Many species can be barerooted at this stage, so in theory you can change all the soil for the new one.
But conifers in general like to keep some of the old soil, so I would mix the two.
But... Suggestions with no data have no value I guess...

I have 2 Aleppo pine seedlings and 1 Norway spruce all 3 are almost 2 years old

So all three can be repotted in the very beginning of the Spring, if no frost will occur anymore after you see they are awake and starting to grow.
You can keep some of the old soil around the fine roots, trim the long ones and eliminate the tap root if it is not the main supporting root (many fine roots branching out from it) of the seedling.
Good luck!

If you are southern hemisphere that would be real soon now, but northern hemisphere reporting would be at least 4 months, probably 6. In either case go to the How-To section of the site here and read up on the details. There may be some videos to watch.