I Would Like to invest in US stock market from UK, Is It Possible?

Of course you can! However, you must open an account with a U.S. brokerage firm. I do not know of any in the UK, but the reputable companies that have the option of opening a U.S. account. You can then invest in the U.S. anyway you want.

On the other hand,
 
If opening an account with a U.S. company will need to complete specific forms to prevent the IRS to take its capital in taxes (I think this way is the W8-BEN, it could be) wrong . There are otherwise no different from taxes on profits / losses of capital based on British law.

Consider this

One of the main corridors should be able to manage operations in U.S. markets for you. In addition, many large U.S. companies are cross-listed on the UK market.