How would you define the level of "processed food"?

Some processing is good and necessary. Some processing not so good. The quantification is even more difficult.

In general, I wouldn't rely on any of such scores.

My approach is:

1) I look at the ingredient list, which already tells a lot.

2) I assess the food quality with my own senses, if possible. Although sometimes color can be misleading.

3) The more bullshit bingo is printed on the packaging, the less likely I buy it.

It takes a bit of experience but over time you get the drill.