It's definitely more difficult to learn the older you get however it's not impossible.
It took me around a year and a half to learn. That's because I didn't do the conventional route of text books and "Lesson one: How to say hello!" I learned conversation versus reading and writing. If you intend to travel there, speaking and understanding should be your FIRST priority. As far as reading goes, just learn Katakana and Hiragana first and you'll be set. I learned my Japanese for travelling in Tokyo and visiting friends and Tokyo is SO foreigner friendly. Everything is in English mostly and Kana and Hira secondly.
The easiest route IMO is start with phrase books. It keeps things exciting and you'll be learning Japanese you'll actually USE. First Japanese phrase I learned? "Do you have a map in English?" Which then lead to learning how to replace map with menu/train schedule/anything I could possibly need in English. I didn't need to learn "Where is the train station?" Because well... the signs are everywhere. Also what will help with translating is as you're learning phrases, what tokus and repeat what they say. (Tokus are written for children so it's the easiest Japanese to get a hold of)
The best thing about learning Japanese is that once you learn how each sound is pronounced then it's CAKE from there. Because Japanese is always pronounced exactly as it's written. And knowing that, it's a lot easier to hear a phrase, write it down, and learn it. Phrase learning is a lot faster and you won't be easily bored out of learning.
The major key is to RETAIN the information. When learning a language when you're older it's easy to lose the information when you don't constantly use it. So make sure you're constantly practicing and everything will be easy. It just takes a LOT of hard work, but if definitely pays off in the end.
EDIT: A great starter book I recommend is "Making Out in Japanese" and "Making Out in Japanese 2". Avoid the curses and vulgar words lol cuz those will get you in trouble. But there's EXTREMELY useful daily phrases in there and even though I speak it well, I still carry around those books for refreshers.