The tank looks nice and simple! I like the natural feel even though there's equipment everywhere(huge sponge there hahaha). You definitely need to know which plants you have. Some plants need certain requirements like lighting and substrate. The level of lighting is important as well, some high lights can destroy low light plants. It looks like you have flourite there so I think that should be fine for substrate. How thick? I believe you need at least 3" on there but the tank is pretty small so it might work out.
Aside from lighting and substrate, all plants definitely need fertilizer. If you don't have any liquid fertilizers, get some to give the plants the macro and micro nutrients they need. Another thing that helps but isn't necessary is CO2. Buying a kit from a store can be expensive so I suggest looking up some DIY(do it yourself) CO2 for your tank; they're easy to do and super cheap!
The timing of your lights when they turn on and off is important as well; it's better if it's always the same. I recommend the lights being on 8-12 hours a day.
