If you mean what can you personally do about a large and politically intractable problem, probably not much. You can volunteer, or donate money to reputable charities. You can vote for candidates that have a realistic plan, if you can find one.
The diversity is so complete there's bound to be somebody you have something in common with.
Don't hold their misfortune in the real estate business against them.
You need a place to shower. Homeless people need a place to shower. Truckers can use showers at rest stops but a homeless person has no place.
You need something to eat. Homeless people need a source of free food. Simple canned food that can be opened and eating without heating such as ravioli works fine. Fruit is fine.
You need a place to shit. Homeless people need public toilet access with reasonable cleaning schedules, soap, and other supplies. (A great use for robots)
You need to sleep. Homeless people need a safe place to crash at night without fear. Outdoor parks that have police protection rather than harassment are needed.
You need clean clothes. Homeless people need a source of clothing. Goodwill clothing ought to be freely available. A place to wash clothing ought to be available.
You need to get selected for jury duty :-) Homeless people need a contact point. The post office should have free postal box numbers so people have an "address".
You need medical help. Homeless people need a way to get the usual medication you find in every supermarket. Homeless people need free access to urgent care like Medexpress.
You need transportation. Homeless people need to get to work. We'll have a couple million self-driving cars on the road next year.
You need money. Homeless people need a source of income so they can get simple needs met.
Being homeless simply means that you don't have a way to accumulate "stuff". Life continues even if you don't have a fixed location.
Society seems to look down on people without a home. This "attitude" is the primary source of problems. Jean Valjean (Les Miserable) was arrested for stealing bread. Is this the kind of treatment you'd want if you needed to eat? Is it cheaper to build a prison, hire police, judges, lawyers, and guards or just make bread free?
The Bezos and Musks of this world can create a million square foot building in a few weeks time but people have to place to go. The Navy has billion dollar hospital ships but can't help a single person. Malls are empty but people sleep outside. Cities could declare "eminent domain" over empty malls to feed, house, and help homeless. Food gets thrown out due to an "expiration date" and people starve.
A fire, flood, job loss, divorce, or illness could make you homeless tomorrow. Provide a way for your future self to survive with dignity.