how to add vertically scrolling text

Can anyone please help to add vertically scrolling text inside of the box?

Like on this picture

You would need to use Custom CSS like this:

.fe-block-yui_3_17_2_1_1704706702897_3535 div.sqs-html-content {
  height:300px;
  overflow-y:scroll;
}

But you would need to update the block ID and size to be relevant to your website.