Why did the US government want to remove the seminole Indians from nation?

Because the US government wanted to keep the citizens safe.

. . . Or because the US government wanted land so that they could cultivate it, use it, build on it and make money off it. The natives were a hassle that the pioneers viewed as savages. Once the Seminoles were pushed away from the Lake Worth area, because the whites wanted to be near all the water, they were only allowed into white towns during specified trading days. The Seminoles were referred to as "dumb Indians" and treated cruelly.

Sure, the government wanted to keep their white people safe, and they wanted to keep the land they had claimed. They didn't see the Seminoles as equal human beings. When the Seminoles fought back to remain on their land, they had every right to. Their land was being taken from them and they were being forced out of their homes so that the US government could expand their territories. People saw Florida as a great opportunity to make money, because everyone wanted to go to paradise. What you should be asking is, "Why in the world did the newcomers think they had a right to be there in the first place?"

It's like walking into somebody's living room and saying, "Get out. This is my house now. Sorry."