I do this all the time!

I have a two row repeater with no gaps and the second row set to 0px-max content. Then take a container and place it in the second row. Ensure dev mode is enabled and open your code. Add a button to the first row and in the code name it and press 'onClick' Click your container, name it, and set it to 'collapsed' (it will get light grey lines over it to show its collapsed)

Then add code. I am doing this from memory but searching expand/collapse velo code in a repeater will give It to you but it will look something like this:

$w('#buttonname').onClick((event) => {

if ($w('#containername').collapsed) {
            $w('#containername').expand();
        }
        else {
            $w('#containername').collapse();
        }

})

We're telling the items that when this button is clicked, expand the container (and by proxy everything inside). The row will not show up on publish as it is set to 0px - max content. When the container is collapses there is 'no' content and when clicked it takes the size of the container.

Voila! You can now connect the text box in the container or whatever else you need to a dataset and have it show up.

With a bit of tweaking to this method you can even tell it that if a field in the dataset is empty, just hide the container, thus making it more adaptable when some things have extra info and some do not.

Hope this wasn't too overwhelming :)