The simple concept is, you can’t just print endless streams of money when you need it, that would devalue it, you can borrow but have to pay back if you don’t then you lose your credit rating and when you need to borrow again interest is charged at a higher rate.
But the simple concept is, as illustrated in the pieces from the BoE bulletin, that I posted earlier, that you can.
We don't borrow money from other countries, we sell bonds , in sterling, to anyone who will purchase them, and the bonds are bought because the purchasers know that they will be repaid. They know we will not default on the debt because we can issue our own currency. The purchasers are people or institutions looking for a safe investment and a guaranteed income from the interest. This has been happening for centuries.
The BoE has been quietly issuing money for decades to ensure that there is enough money in the economy (just as it says in the article). Why do you think that, despite population increases over the years, and increased prices and wages, there is still enough money in the economy to cover it all? It isn't because we've earned it from overseas trade (indeed, have we ever had a trade surplus? More exports than imports?) That's what the BoE Monetary Committee does. It not only controls interest rates, it decides how much new money is to be put into the economy.
Inflation is devaluation. That's why the BoE focusses on keeping it to a low level. That's why taxation exists, to mop up excess money in the economy so that inflation is kept under control. Except that inflation has more than one cause and our current bout is nothing to do with the 'too much money chasing too few goods' cause; it's because the cost of what we buy has, for various reasons, increased. No amount of interest rate increases are going to stop that.
I'm sorry that people don't even believe the Bank of England when it tells it like it is. What hope do I have...?