I recenty got a 10 gallon tank all setup and stocked but I used all plastic plants to decorate, now I'm wanting to replace those with live plants, my question is this, I used 3 gravels mixed together, small black rock, small white rock, and a larger maybe 1/4 inch size tan or natural color. What would i have to do as far as the gravel goes to accept plants? I've been reading and it seems as though all of the plants i'm looking at use something called substrate, can i add the right soil whatever i need to a tank with fish setup

And how do i go about it?
Thanks