Japanese is the world's hardest language!
It's quite possible that someone, somewhere told you this. Is it true? No, not really.
Japanese is a challenging language, no doubt about it. You have to learn a whole new writing system, three of them in fact! Kanji, for the core meanings of words and for names; hiragana, which in simple terms are the threads that link the kanji together, that make them work as a communication tool; and katakana, used mainly to represent foreign words and names.The only people with an advantage being Chinese as their language is also based on kanji, though they are often different and usually pronounced quite differently.
There are 46 basic hiragana and katakana - though some new combinations have come into use recently - and they can be mastered in a matter of days if you're a serious student, otherwise a few weeks. But learning kanji is the one challenge that separates the men from the boys, so to speak. There are almost 2,000 of them in everyday use, and you need to know them inside out if you want to enter a Japanese university, for example. A given kanji can have several, even dozens of different readings, and each kanji has its own stroke order. And remember, this is just the writing systems...
In Japanese, grammar and pronunciation are actually easier to get a grip on than they are in English, though you need to learn to think in a new way. Verbs come at the end of a sentence rather than near the beginning, for example. Something like "To the station I go" rather than "I go to the station". And a sentence often leaves certain things unsaid, having no subject, for example. Pronunciation is phonetically regular, meaning you read it as it's written, unlike English where you have words like "cough", "bough" and "though". There are regional dialects that can confuse even a native Japanese person, but you can get by with hyojungo (standard Japanese) everywhere.
So, where to begin?