It’s easy to set up your English keyboard in Windows to type in Japanese!
Follow the easy instructions in this link, and you will be able to switch easily back-and-forth between typing English or typing Japanese. There are options to type in Hiragana, Katakana and even Kanji.
So, if you know the Japanese word, just start typing it in English, and it will convert to Hiragana.
For example, type “konnichiwa”, and you will get ” こんいちわ ”