Whether you are new to coding or an experienced pro, it is not uncommon to have doubts about what you are capable of or even what you have made already. It is important to realize that you are awesome and the work you put in is something to be proud of.
There are thousands of resources out there to learn the various languages that are involved along the coding road. Stick to one at a time. At times, some of the basics will seem boring and you may feel the need to bounce around to learn more things but avoid this. The time spent working on the small mundane things will stick and you can build on that later on.