A very difficult question.
In the northwest region of Japan, it snows.
People who are not used to snow will have difficulties.
Does it snow in Mexico?
If you don't mind the high cost of living, I would recommend Tokyo.
Traffic is good and you will have no trouble shopping.
There are many foreigners here, so you won't stand out.
About money.
With all due respect, I'm going to assume that you're not a millionaire and tell you what it's like in 東京.
Rents are higher than in the countryside, and the rooms are smaller.
Depending on where you live, you will need 60,000 to 100,000 yen for a small kitchen and a small room.
The appropriate rent for living alone is said to be 25-30% of your take-home income. At my own discretion, I think 300,000 yen a month would be quite enough!
I hope this advice was enough for you.
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