How much i can sell this?

There is something that looks like rust on the T in UNITED on the reverse that might indicate that it is a fake. Try testing it for silver before selling it. If it is real it would probably be worth around 150 USD as seen in the ngc prize guide.

https://www.ngccoin.com/coin-explorer/united-states/dollars/morgan-dollars-1878-1921/17206/1891-cc-1-ms/?des=ms 

If it's a real spitting eagle (and it looks like it is) then anywhere from US $250 to $400, if you get it certified.

This one sold for $400, XF45

This one sold for $240, G06

Didn’t notice that. I’m not that familiar with popular errors on us coinage.