We're on a crusade against unnecessary exterior steps, and most houses have them.
How do you eliminate exterior steps to at least one main level entrance? Shortest answer assuming new construction, site work in combination with moving the house up or down. For retrofits, you're limited mostly to moving dirt or finding an alternate entrance (like through a garage, carport, etc).
The lay of the land determines your options and, in either case, you simply need to plan. If you're dealing with more than a three foot rise, then it's going to be tough but not necessarily impossible.
Why do most houses have steps to the front door? Fact is many shouldn't, certainly not the ones on flat lots. Look at this new house. Notice the lot? I'll add the entire lot to the street is flat, and the house is built on a slab.
So why that ONE step onto the porch and another to get through the front door?
Maybe it's necessary when a house is built atop a crawl space or basement? Nope. For water or bug proofing? Negative. Expense? Ixnay. (Should it cost MORE to build LESS? Actually might be if your builder is headstrong and refuses to do any other way.)
Imagine no steps to climb to the door. Here's how that can look.
You won't get winded getting to your door if you've got ZERO steps to climb. Here are some options if you're attempting to achieve at least one step-free accessible route to either the front, side or rear entry. Access via a garage is another alternative not covered here.
Notice too that gentle sloping and use of retaining walls is aesthetically appealing, you can incorporate landscaping of all types, even raised flower or vegetable gardens and be universally designed in two regards, inclusive access plus easy gardening (e.g. tend your raised garden while seated).
Dirt is your friend. Move Mother Earth, move the house up or down, or a combination to engineer a zero step entrance, the TO part of getting THROUGH the doorway.
Don't throw away useful dirt or rocks! Managing soil on a job site costs money so put every ounce to use. Think of those machines, like dozers and dump trucks, as taxi cabs with a meter. Whether digging, pushing or hauling, a running engine is operator time and ringing cash register. Dirt gets wasted on many projects, particularly when excavating basements, either spread around the lot or carted away. Think of that dirt (and rocks!) as your no-step ramp!