'Learnt' is correct. It is an alternate form of 'learned'.
'Bugger' I'm not sure of, but I suspect it must be slang. From context it seems to be a noun meaning 'nothing'. The only common noun form of this word I'm aware of is one that means 'fellow' or 'chap'.
The verb form is a vulgarity meaning 'to engage in sodomy'. Its use is similar to the use of the word 'fuck' to mean 'engage in sex'. There is a related noun form to mean 'one who engages in sodomy' but it's very rarely used.
The use of 'learnt' and 'bugger' is rare in the US.
Trixie, can you help us out with another meaning for 'bugger'?
Edging closer to the subject topic, WT, I want to point out that you never acknowledged my
post 37 upstring about Thomas Jefferson and his 'wall of separation between church and state'. I think this is important because you claimed that Jefferson's words were taken out of context and twisted in meaning. I want to know if you realize, after reading the linked letter, that you were incorrect.