You will make 1000's of wrong moves when starting out. It's how you learn, hopefully the help from here can get you to harvest the first couple grows so you can learn and get better at growing.
So pH you want your pH between 6.8-7.2 dependent on what type of media you use. Soil likes it a little higher like 7.2 soilless likes it closer to 5.8, hydro idk. Nutes you wanna be following a schedule provided by the nutes you are using. Too much you get toxicities, not enough you get deficiencies. The pH of your solid will help your plant be able to use these nutes. Again the pH range will depend on factors like what the plant likes and the media you use but stay in between 6.8-7.2) . Some media and nute line ups don't require you to pH at all from what I hear but I still pH my water. Your question was a little vague so hopefully I covered a little of what you wanted to know.