I have always suggested two things to new plant people. The first is to start at the easy end and work your way up. I have lovely looking tanks with 1 wpg and lovely tanks at 2 wpg and at 3 wpg with co2 added.
At the most basic end substrate may or may not matter since many of the plants you can use do not need it. Other plants will be fine in almost any substrate once it gets a mulm buildup. On the high tech end substrate matters greatly. (My most common substrate is Estes Bits of Walnut tank gravel and laterite. I also have a tank with fluorite and one with a competing product. All work well.)
As you work your way up the light ladder, fertilizers become the next consideration. The more light you have, the greater the need to suppliment plant nutrients and to do so regularly. Some plants will need fertilizer in the substrate while others can take most of what they want through their leaves from liquid ferts.
Normally there is suffiecient co2 present that you dont need to suppliment it until you cross over the 2 wpg light range. When you approach/cross this point you can start thinking about using Flourish Excel, a form of liquid carbon which plants can use- it is worth about 1/3 of what adding co2 gas would be.
Once into the high light tanks- over 2.5 wpg, co2 becomes a must. Healthy plants come from having the proper balance of light, nutrients and co2. In any tank if one is lacking or in excess the most likely beneficiary will be algae.
The upshot of all this is to spend a lot of time researching plants and planted tanks. Spend time on plant dbase sites such as:
http://www.tropica.dk/database.htm or the dbase section of
http://www.aquabotanic.com . What you are doing there is finding out what plants you like, how big they grow, what their needs are. This will help you decide what plants can work for any chosen light levels.
Other relevant considereations are costs and effort. The more light you have, the more ferts and possibly co2 you need to have, and the greater the cost to set up and maintain the plants will be. Those lovely Amano tanks everybody raves about look that way becuase they are constantly tended- ie fertilized and pruned and water changed.
This brings me to my second suggestion. Your plant plan should be in keeping with your budget and the amount of time you are willing to devote to plant care/needs. A lovely low light tank requires minimal fertilizing and plant care while a high tech tank can require daily dosing and twice a week water changes and constant pruning. Miss some of the work and you can rapidly have an algae covered hungle.
Planted tanks are no different than anything else in life, you start at the bottom and work your way up. Beginning fish keepers learn by starting with easy fish not discus on r/o water. Beginners to plants should do the same- learn to keep plants thriving at 1 and 2 wpg before you worry about doing it at 3 wpg.