MMT
So as to not put all eggs in one basket I highly recommends a listen (audible or you tube) /read Stephanie Kelton’s highly accessible (to us ordinary folk) book called; The Deficit Myth.
A basic explanation of credit creation in a more approachable manner ( Werner can be complex in his language, I often need to mull over things, draw diagrams etc).
Now there are detractors to this and Keltons theories which is healthy, but many that I have read just hold no water and are easily flattened, as to applying gold standard rules to a fiat currency that no longer applies. Gold standard theory works on scarcity of asset and capital loves this as then it just hoards the asset and creates inflation of said asset ie Gold, Land, Real Estate, etc, whereas if government is understood to actually hold the purse strings ( fiat currency, ‘by decree‘) then capitalism is beholden to them and ultimately, us.
Note; only if in a democracy that holds a true fiat currency (note; the Euro from an individual country perspective is not a fiat currency, neither is any currency that is linked to another, ie Venezuela, Arab states and many African states linked to the US dollar, but the UK, Japan, US, Australia, Sweden etc are fiat, yep, it’s messy).
QE
Also Richard Murphy’s book; Money for Nothing and my Tweets for Free
Some good explanations of QE
Further reading
Richard Werner, Josh-Ryan Collins* Toney Greenham and Andrew Jackson
Where Does money Come from? (New Economics foundation)
*Collins was speaking at a Progressive Economics forum where I met Anna Minton