Stacy's advice is sound. Read it twice and do it.
If you are thinking about possibly quitting already, this might not be the hobby for you. Ask yourself, "do I love doing this or am I doing it for some other reason like I thought it would be cool?". If you love doing it, do it. Don't quit because it is hard. It is always going to be hard. You will get better at some aspects in time but you will be challenged in other ways as you grow. Knife making rewards people who are tenacious and who can solve problems. Don't compare your work to others' in frustration. Look to other people's work as inspiration.
Take your time at every step to do your best as Stacy suggested. Learn to enjoy the process of getting the details right. That means making sure your cutting edge is centered, your grinds match in height and shape on each side of the blade, that your plunges are symmetrical when you look at it from the bottom, the center line of your blade is straight and your flat surfaces (ricasso, etc.) are parallel, that your flat ground bevels are flat and not rippled or wavy, that you have removed every trace of the previous grit when sanding before moving on to the next higher grit, that your heat treatment is excellent, that your blade to guard fit up is flawless, and on and on and on. It means taking pride in your work.
You will need some things that are costly but you can make knives with files and sandpaper if you are determined. You can practice your grinding on different materials as mentioned already. I haven't found Home Depot steel to be very cheap at all. But wood, plexiglass, scavenged steel is fine. The material isn't as important as what you are learning. The take away is good grinding technique, safety, patience, concentration, feel, how to make adjustments, etc.
The more you take your time and master the little things the better your results will be. The better your results the more fun you'll have. The more fun you have the more you'll want to stay with it. Before you know it you will be making knives worthy of marking with your name and selling them.
There is a lot of instructional material out there and there are many knife makers. Look for a knife maker within driving distance and contact them. Ask if they give classes or if they would be willing to show you some things. Most knife people are pretty cool people and willing to help.
