Grid with 3 different sizes of tiles in different arrangements based on user choice

Eeb5fu shared this question ago

Answered

I want to generate cards of various sizes that fit together into a 3x2 grid. The user selects which size they want the card to be [1x1, 1x2, or 2x1], edits that card, and then the card is inserted into the grid. How do I accomplish this? Please see attached diagram.