For many of these things, if you are genuinely homeless and have no stable address, there are ways to do it you just have to tell the bank/agency you are working with. However, lying to them is a different thing and for many of these institutions it would be a crime, so don't do that.
IRS: You can specify a different mailing address, but I believe you must provide a home address and sign things under penalty of perjury. Ask a CPA. There may be some way to have a lawyer or CPA file for you and put their address on it instead.
Voting: Depends on the state, ask your local voter registration office. Anti-stalking laws may help you here.
DMV: Nope, they're not gonna let you get a license or tags without an address. Especially if you want a REALID which you can use to take planes.
Bank: Banks are required to have your home address thanks to the PATRIOT act and other laws. But you don't have to have a bank account.
One great alternative to banks is Bitcoin. It doesn't require any ID or other personal information to use. You can't pay for everything with it, but you can pay for some things with it, and every time you do, you help build an economy that doesn't require you have six forms of ID to access it. If you start asking and looking, you'd be surprised how many places will accept it. 20% of Americans own some form of cryptocurrency, 50% of millennial males making >75k/year do. That number grows every year.
Bitcoin has been faithfully relaying transactions for 15 years 24/7 365 without a single hour of downtime or hack. It has a clear fiscal policy it has kept to. The bitcoin ledger, where transactions are stored, is the most secure document in the world and is completely decentralized and politically neutral. No government can force it to do anything it isn't designed to do.
All you need to access it is a mobile phone and an internet connection.
With Bitcoin lightning, international transactions confirm in under a second with fees 100-1000% less than credit cards, often times under a single cent per transaction.
In every major metropolitan area, there are places you can exchange Bitcoin in person for other currencies. You can also do it online. Some of those places require ID, others don't.
Your funds are yours and yours alone. No bank or other entity can lock them up or take them from you. Likewise, there is a limited supply of Bitcoin, so nobody can print more Bitcoin and make yours worth less in the process like is done with every major fiat currency.
Bitcoin's adoption on average continues to grow year after year no matter how you measure it: liquidity, amount locked in lightning, number of nodes, whatever.
For most major retailers online and off, you can buy their gift cards with Bitcoin at exchange sites
And it does all this for less than 1% of global energy usage, often times from renewables.
For a custodial wallet (somebody else holds the funds for you, much like a bank) I suggest Strike. You can easily buy/sell BTC/USD and move between your bank account. Note most custodial wallets require some form of ID and if their company goes under, it takes your funds with it. "Not your keys, not your coins".
For a non-custodial wallet, I highly suggest Phoenix which uses lightning (a layer on top of bitcoin). No ID is required. The downside of self-custody/non-custodial wallets is that when you send your first funds to it, you will need to "swap in" and "make a channel", which incurs a fee for using the BTC layer one blockchain, which is $1-$10 depending on which day you do it. After that, you can use lightning which has the crazy low fees mentioned above. If you don't want to use lightning and your transactions are usually larger and/or rare, you can use a classic non-lightning wallet. All this may sound a bit complicated, but it's because you're already used to all the complication that comes with navigating the banking system. After you've setup your wallet, it will become equally intuitive to you, it's just a matter of dipping your toes in.___-