What is your favorite part of history to read/learn about?

One of the reasons the Nazis could not invade Britain is that they never developed a landing craft. Nothing even like the Higgins boat much less a LST, so they were reliant on capturing intact an English port city. The English were well aware of this and had wired all dock facilities for demolition if invasion became imminent.

Following the Battle of Britain they never again held air superiority, so their tactic of invasion by paratroops as in Greece was out of the question.

I think that's partly true. But also, the UK navy was vastly superior to the Nazis and any maritime landing force would have to deal with the British firepower at sea no matter the method of invasion. The interwar period had shown the great vulnerability of a surface fleet to monoplane airpower - and the Nazis correctly identified that achieving air superiority would neutralize the British surface fleet.

And therein lies one of history's great blunders. The Lufftwaffe identified the strategic objective and had the forces to achieve it. And the first weeks of the campaign were effective - the British radar system acted as a force multiplier but they were still losing. They were losing fighters and pilots at an unsustainable rate and urgent repairs to airfields were just barely keeping them operable.

But the Nazis lost focus and ever-increasingly expanded their target list toward total war rather than defeat of the RAF. They stopped attacking radar stations and airfields in favor of unrelated industrial targets and civilian housing. And that pretty much sealed the failure.

Even had they possessed an effective landing craft, they would still have had to deal with the impact of the failure to achieve air superiority.