Ignoring that random fight, the first thing i would do is a basic bike fiit. Make sure the seatpost height is optimal, handlebar and stem angle is optimal for you at this stage, pedals/clips fit your current shoes. Then, I would invest in a properly fitting saddle (if possible at all, measure your sit bone length). At this stage, you could probably give your bike love for as long as your heart desires.

After that, you can get picky. You can go into clipless, change parts to change the handling (stem, rim width, etc), gear up/down, etc.

Then... Even more picky. Stiffness, vibration damping, more aero parts