How to set a ‘value’ to track events in Google Analytics

I’m having trouble to track the ‘value’ of an event in Google Analytics, since there is no ‘Event Value’ field to be filled in Event Tracker. There is only ‘Event Category’, ‘Event Action’ and ‘Event Label’.

I’m using the ‘Track with Google Universal Tag (gtag.js)’ option to track clicks on buttons, the events are already being recorded in Google Analytics (so the integration is working properly), but I can’t find a way to set a ‘value’ to these events, and Google Analytics is registering “zero” value to all these events.

I’ve set a ‘goal’ in GA, and my intention is to use the option ‘Use the Event value as the goal value’ (as explained here: https://support.google.com/analytics/answer/1032415 ), so that each button click could have a different value assigned to it.

Any help?! ??