What specs to look for in solar panels to know it can power a product?
You need a different pump, and you need help speccing it.
You lack enough knowledge about electricity to be able to design a system, spec a pump, and certainly to build it in a way that would work.  You'll either need to skill up, or get help.
Right off the bat, the pump you picked uses 120V AC power - the zappy kind that can kill you, and that you buy from the power company.
If the goal is to go solar, you probably want another kind of power, called low voltage DC power, commonly 12 or 24 volts, and that is the kind that is used in cars.

You would need to identify and purchase a pump which happily ran on that voltage and type of power.
Usable solar panels already provide that type of power, so that part is largely done.
It won't be hard to add a charge controller and battery if you wanted to bridge across cloudy moments.