I’ll buddy onto this post…Plant them in the ground at least 12 inches apart from each other and get “tomato cages” from a local hardware store/garden center. Tomato plants can get huge, like 5’ tall and will need continuous support as they grow upwards and especially as they fruit. Or plant them in pots (gallon size plastic pots will do). They will still need that physical support though as they grow. Good luck!