Welcome to the site! :)
You can use several kinds of nutrient products, with the best results coming from ones that are more "cannabis-friendly", such as Canna, Fox Farms, Advanced Nutrients, General Hydroponics, and many more. They can be purchased online or at a hydro shop. Each company has usually two or three different bottles that you will, and instructions for mixing them into water with weekly dosages on their websites. It's usually a good idea to give plain ph'd water every once in a while, maybe every third watering. One thing to keep in mind, is that each plant from seed may have different needs in terms of watering and nutrient uptake.
There is a lot of info here, especially in the grow logs and other threads about nutrients. The search function is OK, but even better is to use google and type in: cannabis nutrients site:boards.cannabis.com
This guide is also very helpful:
Grow Guide Crtl + F and type in nutrients.
What kind of lighting setup were you planning on?
Happy growing :jointsmile: