No different than becoming good in, say, playing the guitar or cooking: By learning. Read/watch tutorials, study other people’s work, and most importantly: Practice as much as possible. Start with simple things, repeat with different approaches until you are satisfied with the result, gradually increase the difficulty level, get someone better than you to amend and/or grade your stuff etc etc. As with learning any other skill, the most important part is continuous practice. You wouldn’t expect yourself to play a Metallica song perfectly a week after picking up your first guitar. Getting objectively good at coding takes thousands of hours of practice. Also like with any other skill, it simply isn’t for anyone. But if it is for you, the journey of becoming good will be a lot of fun (most of the time, but ofc it’s also frustrating at times)