To create a message query, We'll need to let data explorer know we want to see messages. Select "Add" in the view area.

Open the dropdown by clicking "Select..."

To add a filter to messages, select the ellipses on the right hand side

Select your filter. Here we'll want to see incoming messages so we'll select "Incoming"

To make sure we we want to see only incoming messages, select the dropdown

By clicking "true" you will be asking for messages that are incoming

To change your visualization option, click the dropdown in the top right-hand corner of the card, which has a default visualization of "Line" AKA line chart

Select a visualization option, here we will select "KPI" to see the number of messages as 1 number

How to create a message query