There is a link to good beginners plants in my signature. I have had success with most although find Amazon swords to be a real pain to keep going, even with the root fertilisation that they need. Most of the plants in that link will grow fine with just low light levels which are around 2 watts per US gallon but they will need at the very least a basic liquid fertiliser once per week. I use Seachems Flourish although there are other general liquid ferts which are fine to. Ideally you should be dosing it daily or at least every other day, not in one big lump at the weekend. I dose every other day roughly splitting the amount recommended per week across the days I'm dosing on. This provides more stable fertiliser levels and less chance of algae / bacterial blooms. That's about the minimum you can get away with if you want to grow decent plants. Carefully removing them from the pots and wool before planting is also important. For better growth the next step to add is liquid carbon, something like Seachems Flourish Excel although again there are others. Dosed daily will provide a similar affect to having a dedicated CO2 system which all plant enthuasiasts live by. Finally you can improve your substrate with something like Eco Complete which provide numerous trace nutrients. I have got by growing most of the plants from that link with just the first 3 mentioned above: 2wpg light, liquid fert every other day, liquid carbs daily. If you want to grow more difficult species then more light and a fermentation / tank based CO2 system are needed as well as an improved substrate.