How to make a firm loaf from pancake batter mix? I have two questions. One specific. One general.

First:
I am a beginner at cooking. But, I have learned a few things. I try to experiment without going crazy. I have found that altering a recipe can be a good thing at times. Here is one thing that I have tried recently that I'd like a little bit of help with:

I have some boxed pancake batter mix. It is pretty good. (Sometimes you have to get out of the house quickly and early in the morning. Sometimes convenience is more important that making something from scratch. That is one of the trade-offs with cooking, right?)
I made a loaf with the box mix. It came out soft, like pancakes. No surprise. That result is fine. It tastes good when I pop a slice in the toaster oven in the morning. And, the toasted crust that forms is kind of nice.

Like I mentioned before: I am a bit new to cooking. I don't know all the nuances. What can I add to the batter mix to firm it up? I think it is eggs. But, I'm not sure. 

Edit/Added: The loaf mixes and "from scratch" muffin batter loafs I have made in the past were denser. This loaf from the pancake mix was more cake-like. I want it a bit denser like the muffin batter loaves.

Secondly:
Where can I learn about things like this? I have what I think is a big good basic cookbook. It has instructions about all the different cookware and utensils. It has listings of cooking terms and what to expect with different herbs and spices. It also has a section at the end of each chapter about how to cook things like different cuts of meat and how to choose the right baking pan. But, I can't find out how to firm up batter.
Just use less liquid, that should work.  Since you didn't mention the brand, you have to wing it at first.  If you want to be a good cook, get am old cookbook and follow the directions, you can experiment after you've learned how.