That's a very large topic, so in this limited space I can give you a good overview and then some resources for further research.
The goals of the Spanish Empire are often referred to by historians as "Gold, Glory and God". That is, they developed their empire in the Western Hemisphere because of the large deposits of gold and silver they could exploit, which in turn paid for their empire, funded aggressive and widespread missionary work on behalf of the Catholic Church, and made the Spanish military and navy the most powerful and feared on Earth. However, large numbers of Spaniards did not settle the New World as the British later would.
The British, on the other hand, established an empire in North America not because of religion, but because of cash crop potential. They may have wanted to find gold, but since little was available in their colonies, they went another direction that was ultimately very profitable as well. By contrast to the Spanish, they were not looking to save souls or convert the Native Americans to Protestantism, rather, native peoples were exterminated and pushed west as part of the policy of the crown, and to make way for more settlement and increased plantation cultivation.