I'm looking at a generator for the house to run the essentials and trying to size what I need. One of my first concerns is the well pump since no electricity = no water. Only thing I can find in the well house is this box with the serial/capacities on it. Any thoughts on what this pump draws and start up watts? I know its 2HP at 650ft depth

A 30 amp breaker means the pump is smaller than 2 hp will use ~13 amps/2300 watts during operation and will require a 4 KW internally regulated generator to operate the pump. (This size breaker is also used for 1.5 HP pumps which require a 3 KW internally regulated generator for proper pump operation.)
A 40 amp breaker means the pump is smaller than 3 hp will use ~16 amps/3200 watts during operation and require a 5 KW internally regulated generator for proper pump operation.
A 50 amp breaker means the pump is smaller than 5 hp and will use ~25amps/5300 watts during operation and require a 7.5 KW internally regulated generator for proper pump operation.

Thank you both! Based on the two replies, I got what I needed. I'm pretty sure I actually have a 1.5hp pump also