Doubt in ODK Build

Hi @Agustin
We're glad you're here. When you get a chance, please introduce yourself on this forum thread. I'd also encourage you to add a real picture as your avatar because it helps build community!

Have you seen the documentation about the grid of selects: https://docs.getodk.org/form-question-types/#grid-of-selects-on-the-same-screen
that should help you.