Hi,
Yes this is easily possible: have the button connect to a microflow, include the entity you would like to alter as an input parameter, and change the attribute value using a change activity.
I’d suggest going through (at least the start of the) Academy Learnings, all Mendix basics are covered here so you start developing functionality. Good luck!
You could create a microflow (or a nanoflow) and set it to execute once an user presses the button. In this microflow you can put a ‘change object’ action in which you change the attribute. A possible way of doing this would be:
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It's up to you then to decide whether you also need to refresh/commit the object.