Like many side scrolling airplane games, the object controlled in this game behaves a lot more like a rocket than an airplane. I suggest learning a little about the physics of airplanes[1] to improve the feeling of flying.
I made a prototype[2] once (not working on mobile, unfortunately) to show what can be done, and it takes getting a lot of details right![3]
[1]: http://av8n.com/how/
[2]: https://xkqr.org/flightle/
[3]: https://entropicthoughts.com/sidescrolling-flight-simulator
Second this. I've been trying to build a casual flying game in unity and getting the physics right is hard.
What I found particularly hard is simulating accurately how gravity works against the aircrafts momentum, and trying to get stall and recovery right