m looking for a site that pay btc to watch video...suggest me if u have any 
There used be a couple of high paying "watch videos for BTC" sites, but they are long dead now. Existing ones does not pay much. Apart from watching videos, if you can do micro tasks then I would recommend:
http://www.bitcoinget.com
http://4bc.co (TE + watch videos)
http://www.bitcoinreward.net
You can also get some satoshis through bitcoin PTC sites, btcclicks, coinadder, bitter, btcvic, ads4btc, clix4btc, world-of-bitcoin, adbtc. All these are legit and paying.
It appears PTC sites are growing up in the bitcoin arena. When I first started with bitcoins in 2012 there were none of these, all started after the spike of bitcoin price in November 2013. I am glad that bitcoin is being implemented in many areas of online earnings if I can call PTC earnings. I will try some of these, if done through multi tabs ,nowadays every little satoshi counts.
If you OP still need website to watch videos, they are not worth it, better to use a faucet rotator , it will be more time consuming but it will earn you more satoshis in a day.