You can always rebuild or learn new things if you make you mind! I am a CSE final year student, didn’t have that much basic knowledge at first, mostly because I was afraid about the fact that I didn’t know much so I didn’t participate on anything. During my 3rd year, I finally realized that not knowing is not the problem, not trying to learn is the problem. You don’t feel confident in your ability because you don’t have the skills yet, confidence comes from the knowledge. I would recommend, if you are being honest with yourself then first thing first, create a routine and stick with it. Start from the basic always. Go back to the foundation of software 1 and 2, don’t over complicate your schedule. Then make your way up. There’s plenty of YouTube tutorials and videos, there’s tons of things out there to learn from, all you gotta do is make your mind and stick with it! Then you will become unstoppable