Hi @jamal,

Unfortunately it's not possible to view who has upvoted. For the most part, upvotes are used to increase visibility of an answer to help the next person who has a similar question to easily find a solution. (Same with accepting answers)! For Ideas, upvotes help to drive product development by informing us of how many people want a certain functionality.

Receiving upvotes on your answers or comments then give you reputation points as a user. There's a bit more information in this article: New to the Community? in case anyone wants to take a deeper look at it.

What I wanted here is to have a “like” tool as it is available in Geonet forum of ESRI.