What is Wales alphabetisation?

It's complex, as some letters that exist in English do not exist in Welsh, whereas others that consist of TWO letters in English count as a single letter in Welsh.
Generally speaking, the Welsh alphabet is the same as that of English EXCEPT that some letters don't exist in it- these are J,K,Q,V,X and Z (the only exeption to 'J' being when the name 'Jesus' is spelt, whereupon it's prounounced 'Y').
On the other hand, the two-letter combinations 'LL', 'HL', 'FL' and 'FH' count in Welsh as a SINGLE letter.

It's curious that Welsh is a related language to Cornish, which includes all the letters omitted from Welsh apart from 'X', It's said that the Welsh and the Cornish are said to be able to understand each other's language, but as a Welsh speaker whose tried to converse with a Cornishman, I've had great difficulty. I think that the Breton tongue is closer to Welsh than the Cornish one.