change the front brake pads on my truck and now when I apply the brakes the pedal seems spongy

This sounds like you have air in the lines or the pads are not set properly.

Here is a guide that will help with bleeding the brakes:

https://www.2carpros.com/articles/how-to-bleed-or-flush-a-car-brake-system

If there is no air in the lines then we need to make sure you installed the pads correctly because I suspect the retaining clips may not be holding the pads in place.

Here is a guide that talks about this in more detail:

https://www.2carpros.com/articles/how-to-replace-front-brake-pads-and-rotors-fwd

Below is the process from the manual on how to replace them as well.

Let us know if you have questions. Thanks