What’s the correct image form factor for title to be showed properly?
I’m not sure if your question is how to display the image fully ? If so you may add an image component and select “show the full image”. This will display the picture 100%.
Please let us know
Typically with most components that contain an image, your image would have to match the same ratio of the container to display the entire image. In your case, the title component is set to a square, so an image with a square ratio would work best. The exception, as @AymenM pointed out, is that an image component will allow you to display a full image regardless of the image’s ratio, but you may lose some of the other options, like having a title and a description.
You can view the images guide to learn more about working with images.
Adding images - Glide Library.
If it were me, I prefer the flexibility of using a tile to display an image with text instead of a title component or image component. To do this, you need to create a multiple relation in your data that links your data back to itself. This works best if you have Row IDs enabled on your sheet. Just link the row id column back to itself, so you always have only one match. Then you can use that relation to add an inline list on your screen, set to the tiles layout. This gives you all of the text overlays that are available for tiles as well as different image ratios that may help to get your entire image to show.