How to report your problem productively in the Unity3D forums:
How to understand compiler and other errors and even fix them yourself:
If you post a code snippet, ALWAYS USE CODE TAGS:
How to use code tags: Using code tags properly
Also, consider this:
How to do tutorials properly:
Tutorials are a GREAT idea. Tutorials should be used this way:
Step 1. Follow the tutorial and do every single step of the tutorial 100% precisely the way it is shown. Even the slightest deviation generally ends in disaster. That’s how software engineering works. Every single letter must be spelled, capitalized, punctuated and spaced (or not spaced) properly. Fortunately this is the easiest part to get right. Be a robot. Don’t make any mistakes. BE PERFECT IN EVERYTHING YOU DO HERE.
Step 2. Go back and work through every part of the tutorial again, and this time explain it to your doggie. See how I am doing that in my avatar picture? If you have no dog, explain it to your house plant. If you are unable to explain any part of it, STOP. DO NOT PROCEED. Now go learn how that part works. Read the documentation on the functions involved. Go back to the tutorial and try to figure out WHY they did that. This is the part that takes a LOT of time when you are new. It might take days or weeks to work through a single 5-minute tutorial. Stick with it. You will learn.
Step 2 is the part everybody seems to miss. Without Step 2 you are simply a code-typing monkey and outside of the specific tutorial you did, you will be completely lost.
Of course, all this presupposes no errors in the tutorial. For certain tutorial makers (like Unity, Brackeys, Imphenzia, Sebastian Lague) this is usually the case. For some other less-well-known content creators, this is less true. Read the comments on the video: did anyone have issues like you did? If there’s an error, you will NEVER be the first guy to find it.
Beyond that, Step 3, 4, 5 and 6 become easy because you already understand!