Basically, yes. What matters is the total amount of that currency, and if they just make more, whether digital or not, you get hyperinflation

Absolutely. That business can then transfer it to someone else for goods and services, aka use like any other money. It's out there in the wider economy behaving like normal money.

So for governments to take on debt without completely fucking over their economies, the money can't be just poofed into existence. It must come from already existing money. The US, for example, borrows money from people by selling treasury bonds. Basically, promises to return the money plus interest over x years.

Money is really “printed” anymore. Atleast not in a way that’s meaningfully inflationary. Money in printed through the issuance of debt. More gov debt, the more money supply.