hoping he is a molly.
That's a platy
Platy. Edit: BottomDweller beat me to it.
It's a platy.
It is a male Platy. Very easy to distinguish from Mollys. Mollys are more elongated while Platys are more stocky. Molly´s caudal peduncle isnt as thick as the one your fish shows in the pic too. Because your fish´s caudal peduncle is so thick I would say it is has the form of Xiphophorus maculatus or the southern Platy. There is another body form, the Xiphophorus variatus form which looks like a swordtail without a sword. Xiphophorus variatus comes from North Mexico (Tamaulipas and Veracruz) while Xiphophorus maculatus comes from South Mexico and Central America (Tabasco, Oxaca, Chiapas Campeche and Guatemala) Notice how I said "form". Your fish isnt a true Xiphphorus maculatus, ornamental Platys are a mix of Xiphophorus maculatus, variatus and helleri (green swordtail) but they are often times bred to resemble either the maculatus form or the variatus.
Welcome to fishlore! I agree, platy.