I think you have a few concepts merged together.
IP generally refers to "interlectual property". Which put simply is something you know that others don't that gives you an advantage. In my case this is the algorithm for optimally placing ads on a newspaper page.
Product is a thing you can sell, normally containing the IP, but which also has a bunch of very standard stuff as well. In my case user interface similar to InDesign to let people work with the IP and, more importantly from their point of view, get their job done ... Either saving them money or making them money.
Your question asks "what do I do to build a ip/product company?"
so the answer is, start a company, build a product, put a price tag on it and sell it to someone who will get benefit from it. If your product has some special aspect, process or unique element then you have some IP.
I am guessing your real question is why do I care about IP?
The answer being that competitors or larger companies are more likely to buy your company rather than work it out themselves... Thus it has value along with your ongoing revenue from support and your client base (their chance to sell other stuff to the same people).