Наврать с три короба means not just 3 simple boxes of lie. But BOXES.
Короб in old times was a kind of big volume backpack made from braided bast, or the same size home storage box.
So "с 3 короба" is the really BIG portion of lie, and "с" here means not "from", but "around/about" regarding qty.
Another interesting idiom is он врёт, как дышит - he's lying like breathing, means lie as usual and natural way of someone's behaviour.
"Из аз этой короны." - just mix type and illiterate. Should be "из-за" - "because of". Корона most probably is shortened word "coronavirus" here.
All the world's Kremlin,
And all the men and women merely agents