You can, but it's not easy. You'd have to be able to find the roots and then remove them from the pot, then replant them into a new pot of soil, preferably with some compost mixed in as well.
It's a good idea to start with a small plant, and then build up the amount of potting mix. You should use as much potting mix as you need for the size of the plant you are growing. It's a good idea to make a couple of small pots to test out your plants first. You can put the plants in the soil, but it will take them some time to adjust.