Is there any Subgroups in Christianity?

Yes, certainly. You've got one big division between the Catholics and the Protestants. On the Catholic side there's the division between the Roman church and Eastern Orthodox. On the Protestant side there is a large number of denominations, from big sects like Episcopalian, Baptist, Methodist, and so on down to tiny groups hardly anyone has heard of. And some of those groups have splitoffs within them. You have your Quakers, Shakers, and Pentecostals, and you have your Presbyterians, Congregationalists, and Nazarenes. You even have your Unitarians. The list goes on. As the saying goes, many rivers to the sea.