Proper noun
にほん
にっぽん
日本のカレーはおいしいです。
Japanese curry is delicious.
十月から、日本にすみます。
I'm gonna live in Japan starting in October.
日本のかたちをしたケーキをやいた。
I baked a cake shaped like Japan.
Remember the secondary meaning of 本? It's "origin." So, this word technically means "sun origin." Does that sound familiar? Japan's known as "The land of the rising sun." That's why Japan comes from 日本.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well, though take note that the 日 portion is shortened a bit. So instead of being にち it is just に.