Although America has no official religion and is known for its "religious tolerance" founding ideals, Christianity is, by far, the most prevalent religion in the United States. Next to Christianity, most studies show that Judaism and Buddhism are most popular.
Even so, there are many different denominations or sects in each of these religions, such as the various Protestant churches along with Orthodox churches and Catholicism just within Christianity.
Shintoism, Buddhism,and Confucianism are the three main religions in Japan.
   
Roman Catholicism
If you mean Taoism, then one of the other religions is Budhaism.
Christianity/catholic
The three main religions of the Great Awakening in 18th-century colonial America were Congregationalism, Presbyterianism, and Baptism. These religious movements emphasized personal religious experience, emotional expressions of faith, and a return to traditional religious values.
Catholic Christianity is very widespread along side the Indigenous Traditional Religions
Judaism, Christianity, & Islam.
jewish, christian, and islamic
Islam, Buddhism, Catholicism.
Judaism, Christianity and Islam
They have three main religions Christianity, Islam, and African religion.