Most people don't hit their daily fiber target. The general recommendation is somewhere around 25-38 grams a day depending on age and sex, and a typical Western diet of white bread, processed snacks and not much fresh produce lands well under that.
Dates
A single medjool date carries about 1.6 grams of fiber, and because they're eaten dried and whole, skin included, that fiber comes packaged with potassium and natural sugars rather than anything added. Three or four dates chopped into oatmeal or blended into a smoothie add up faster than most people expect.
Apple
An apple, skin on, gives you close to 4-5 grams of fiber. Most of it sits in the peel, so peeling the fruit before eating it cuts the fiber content substantially. Apples paired with dates make a simple fiber-dense snack — chop both into a bowl with a spoon of nut butter and that's the whole recipe.
Avocado
One avocado holds roughly 10 grams of fiber, more than most fruit by weight. It's also mostly unsaturated fat, which is why it works well swapped in for butter or mayonnaise on a sandwich rather than eaten as an extra.
Beans
Dried beans, black, kidney or pinto, run 6-8 grams of fiber per half-cup cooked. Soaking them overnight before cooking cuts the cooking time and makes them easier on the stomach. Canned beans work too; rinse off the liquid first to cut the added sodium. For a shelf-stable option that needs no cooking at all, a handful of nuts and dried fruit covers the same ground.
Building the habit
Adding fiber too fast causes bloating, so increase it over a couple of weeks rather than all at once, and drink more water as you do — fiber needs water to move through the gut properly. Swapping one processed snack a day for a piece of fruit or a handful of dates is an easier starting point than trying to overhaul every meal at once.