You need to buy seed starting mix. It is inexpensive. It is sterile. You can make it yourself if you choose. If you make it yourself you should follow 1 part peat moss: 1part vermiculite: 1 part perlite. You can exclude 1 of the latter two. You would also need to put lime in the mix to manage the ph of the peat moss. I used to make it. Now I just buy it on sale. You also need a seed starting tray.
Fill the tray with seed starting mix. And this is important, pack each cell of mix down with your thumb and refill. You want to make sure the mix is nicely packed in each cell. I you don't your seeds can drop to the bottom. I prefer to have a lot of seed starting mix in each cell because I over plant my cells.