Is it a soil grow? Feed when the plant needs it or build it up from a small amount, that way you can see how the plant responds, less is better than more to start with, mix quarter strength and less for small plants and apply to one watering only to see if it has a positive or negative effect. Most small plants in soil do not require ferts till they have depleted up the nutes in the soil a little and by this time you should notice a lot of roots sticking out of the bottom of the pot, could also repot and hold of the ferts for a few weeks if the plant has filled the pot with roots and been in it a while.
What are the numbers for the NPK, which stand for N-Nitrogen, P-Phoshorous and K-Potassium, should be three numbers like 6/5/3 or 4.5:2:7 or similar, the numbers are the value of the nitrogen, phosphorous and potassium. The other nutrients you shold be aware of are calcium and magnesium. These five are the main ones then theres stuff like iron, boron, manganese and loads other. These can be called trace elements or micro and macro nutients. Seaweed has a lot of these in but not much magnesium. The ferts sound pretty good and standard so don't panic by all the new words and terminology, just do some reading up on ferts and nutrients also NPK values as you generally need a different fertilizer for veg and flower. You will have a lot of questions that researching and googling plus previous threads will help you with too. Hope this is a start for you and good luck, its never easy in the beginning.