How to always see all band values with Identify Features of QGIS?

If you have the bands separately and you want that when consulting with the identification tool it shows you the value of all the bands. You have several options.

1.- The solution for your case is: Go to the bottom of the Identification window, in the View option select Table, it will show you the name of the layer, the band, and the pixel value for that layer.

2- Other option is to create a virtual raster, it's a layer joining all the bands but without creating a new file.

When consulting it will show you the pixel value of all the raster layers

You can use the Raster Value Tool to do this.