Looker Studio Table with interactive Checkbox column

I'd like to create a Pipeline table that has a checkbox column which can be ticked in order to create a sum so you can instantly see what value from the Pipeline to commit to forecast. Hence, the table would need to be interactive.

The optimal solution would be that this sum can also be used as a metric, e.g. to deduct from the current Gap to target or to add to the current Bookings and divide by the target.

Does anyone know any solution that could accomplish this?

Honestly I have not tried anything specifically yet as I do not have a clue where to look at.

Thanks a lot and have a good weekend, Stefan