Just make sure it doesn’t have feed in it already, which a lot do. Any basic garden or potting soil will work as long as it’s not full of feed already. Seedlings can’t take any fertilizer from the start. It’ll be a week or two before you would need that and then just a diluted version.
You can use outside dirt if it’s rich. You would need to add some Peat Moss to it to make it more airy. Dirt that is too compacted is not good. peace