Please Help Me Idk What to do!

I have 3 outdoor plants and then one plant that im growing indoors with a cfl and a small t5 flourecent light.The main question i have is are there any fertilizers that will work well for the plants that i can buy from a local garden store and the other is that the one plant indoors has a little brown at the tips of 2 leaves and dose that mean there too hot? please help

got any pics?

if they are still in the vegetative state i found all purpose Miracle-Gro plant food works, just mix it with your water. But as soon as they reach flowering you wont wanna use that. when they reach flowering the need more Phosphorus and less nitrogen you cant tell the amount of each by the numbering on the container of fertilizer. Miracle-Gro is 24-8-16 which is 24% Nitrogen and 8% Phosphorus and 16% potassium. which is decent for vegetative growth. flowering will use a lot less nitrogen.. unless you want some shitty leafy buds

thank you so go with a miracle grow that is 24-8-16.....are there any other ones that will work better that i can get at the garden store and what am i looking for more nitrogen and potassium?