You should learn communication using easy-English rather than try to master Japanese.

You can get along in Japan with only easy-English.

There are a lot of workers from English-spoken countries in Japan.
But most of them can hardly speak Japanese.
They basically get along by English and a few Japanese words (mainly greeting words).
It’s OK in Japan. Japanese people never impose on you to speak Japanese because they know English is global standard and it’s too difficult for foreigners to master Japanese.
But you have to use easy-English. English speakers working in Japan well know it. Of course, average English level of Japanese is low, but there is few can’t understand English absolutely. To speak easy-English is easier than to master Japanese, isn’t it?
When you travel around Japan, it’s enough to keep in mind this fact.

In addition, I show one example below.
My former English teacher (he is a nice British man) couldn’t use Japanese. And he use only English in lesson and daily life. But he could talk at proper English level for people in front of him. Therefore he could communicate Japanese people around him and also some Japanese girls had special feelings for him (but he didn’t seem to like Japanese girls and he came back to England alone).