Bullet Drop Graph

I need help on graphing bullet drop
The only factors it should only contain is the gravity(196.2) and the horizontal velocity of the gun
image

I’ve honestly just used some formulas I found online without understanding a single thing of what it does and if I do found one it looks like it gives similar results from higher velocities to lower velocities

I assume you want position relative to the sight line like this:

If you only want to consider graivty and bullet velocity then you have to assume some default sighting setup. If you have a typical setup like in my picture, then your chart looks like it could be right.