The native Japanese word for milk is pronounced nyuujuu or chishiru or chichishiru per Japanese Wikipedia, but miruku (note, short “i” not mii) is a common usage. The “why” is probably complex.
Japanese does have some non-Japanese or Chinese root words that are pretty old. Bread is “pan” from Portuguese “pão” (Portuguese note: that’s nasalized so it’s not too far off).
I’ve always pronounced Sao Paulo as ‘sow- [like a female pig, or the first part of ‘sauna’] pow-lo’, but when I hear some other people speak it, it sounds like ‘san pow-lo’. Any guidance on this?
Welsh is cwrw, which is distantly cognate with cerveza. There’s an Irish cognate, too (cuirm), but I can’t remember if it exists in Modern Irish.
You are not a Paulistano 
You want to be at 8:20
Sort of, yes. Most commonly in the word “ceolchoirm” meaning a concert. Coirm drifted semantically from its primary meaning of “beer” to meaning a feast and then festivities.
James Thurber told an anecdote about being at a Paris café during WWI with a friend who asked for “beer”.
The waiter brought him this.