>>1271360If you just want to try your hands at gardening and not fully commit straight away get some 30x30x25cm gardening bags (Pflanztaschen)
>pic related. They hold about 22l of soil, thats a bit larger than the typical US 5 gallon bucket so it's perfect for one tomato or up to two peppers per bag. A pack of two goes for 3.50€ at Hornbach and will do the job. Just fill them with ok tier gardening soil and you're ready to plant.
If you like it you can start building raised beds in fall when gardening stuff usually is on sale and if you don't like it they're easy to get rid off.