Familiarize yourself with adding actions to buttons. 

The command to change object visibility is show

The parameters are;

• val=<visibility> 
• scene=<scene name> (case sensitive)
• group=<group name> (optional)
• delay=<time in ms> (optional)
• <scene item> (case sensitive)
• <scene item>
• <scene item>
• ......

The val parameter can be one of : 0 (hidden), 1 (visible) or  * (toggle current visibility)

The scene parameter is case sensistive, so must be exactly as it appears in OBS.

The group parameter must be used if the scene item is in a group (available from OBS Studio v22).

The optional delay specifies a time (in milliseconds) to wait before running the command.

You can add as many scene item parameters as required.

Example - toggles the visibility of two objects: News flash and Phone banner