When/if using the bulk chemicals (powder), you will find this calculator invaluable: Rotala Butterfly | Planted Aquarium Nutrient Dosing Calculator
However, as a beginner, you might find it easier to first start with the bulk chemicals: KNO3 and KH2PO4 for the nitrate, phosphate and potassium (the macros: N, P and K). If you decide that you need more potassium, you can add K2SO4. Many of us measure NO3 and PO4 to determine how much of the N and P is needed, since our fish food (via the fish poop) often provides enough. So, if we cut down on the KNO3 and KH2PO4 because of this, we may need to add some extra potassium with the K2SO4.
For traces, I would stick with the Flourish as it contains all the traces (including iron, although you may need to bump the iron a little) that you will need but, again, use the calculator, above. Depending upon which way you go: PPS or EI dosing methods, the calculator will then help you select the quantities to dose. Once you get used to using bulk chemicals with the N, P and K, you can move on to bulk chemicals for the traces, if you wish. It can be very low cost.
The Excel cannot be purchased in the powder form and is very good for low-tech (no CO2 injection) tanks. There are other options, such as Metricide 14, but I'd stick with the Excel for now.