I would start with substrate: depends on the gravel size, smaller is better. Check the stickies under Substrates section for an intro. Root tabs will certainly help, you can buy Osmocote+ DIY tabs from people on TPT for a fraction of 'brand' names.
You can certainly use your existing light, I would switch actinic bulb for either another 10K or for a ~6,500K.
Check out members' journals and the tank gallery, take notes of the plants you like, find their names and look them up. The WTS section of the forum is a good place to get plants. Don't overlook the RAOK section: you can load up on a ton of plants for a nominal cost if shipping.
As all if us, you will learn as you go. Don't be afraid to ask questions. This forum is a great community and a huge library of information. Use it.
Courtesy * Integrity * Perseverance * Indominable Spirit * and Self Control
Tenets of TKD