Thank you for your feedback! I'm really touched to receive such thoughtful and encouraging comments on my first attempt at making a game! Regarding the issue with the health bar, you're right that I haven't optimized the UI well enough. I'll work on improving the display of both the player's health and the boss's health in the next update.
As for the camera... it's true that I wasn't sure how to adjust it on my first try, but the tutorial you provided is really helpful. I'll try to implement some camera movement, and this will definitely be a direction for improvement going forward!
Regarding the bullet hell level design, I was pleasantly surprised to find that the code in the tutorial is actually understandable! This is something I couldn't have imagined a month ago. The bullet-dodging mechanics are really fun, and I originally intended to design obstacles as textures that could be used to dodge boss attacks, but I didn't have enough time to write the code for it. I'll definitely consider this gameplay direction in future designs!
With your encouragement, I truly feel motivated to continue making the game! I'm so glad you like my character, and I really want to finish telling her story! Honestly, typing this out has moved me to tears. Thank you again for your thoughtful feedback!