>>1407580The right tool for the job makes work much easier. The height and length of the blade will help determine what you can do with it. So, a small pocket knife will let you do more detail work, but will suck for big material removal. While a fixed blade "survival" knife will such at most things that are not big material removal. A fixed blade chip carving knife will be perfect for most whittling jobs regardless of need...unless you are making spoons.
You can do a lot with a medium-sized pocket knife. Your inexperience only limits your knowledge of what tool is best for various jobs. Having the right tool will make it much easier for you to get better and you won't be as frustrated.