What fish is this ??

[Jayjay5573]

 

[PheonixKingZ]

Hello and welcome to the forum!

Looks like a Platy to me:

(https://aquariumtidings.com/platy-fish/)

 

[Flushable Pets]

Welcome to TFF! Looks like a red wag platy.

Edit: Pheonix beat me to it.

 

[Essjay]

Going by the second photo, it's a male red wag platy.