If you are aiming for something like this, you could use a container around whatever you are going to make scrollable. add a class (scrollcontainer in this example) to it and use the following css to apply a basic style to it. Check out Calypso if you need to know how to apply css first. ( https://docs.mendix.com/howto/front-end/calypso )
If you want to do it ‘quick and dirty’ you can also add what is within the { } of the following css to the ‘Style’ field of the properties.
.scrollcontainer {
height: 250px;
overflow-y: scroll;
}
Modeler:
Container properties: