What can I put on the ground outside in front of my living room window to make an inexpensive porch area?
There are MANY types of pavers available. Make a good solid base with compacted sand, lay your pavers, and then fill the cracks with a polymeric sand that will harden after getting it wet.
Least expensive would be to mix up ready mix in a wheel barrow and pour. You will want to level out somewhat first and make a form with wooden 2x wood. You can also by forms and pour it to look like rock.
You could try a gravel patio - if you don’t mind the texture. It’s definitely most affordable.
Concrete stepping stones, comes in several sizes and 2 or 3 colors depending on availability. Can be done in one day. Easy, fast, low maintenance and inexpensive. Pouring concrete is an art. If you don't know how to do it properly, it will come out looking like a lumpy bumpy mess.