danda i need this for running my own btc wallet service.
bitcore = bitpay's bitcore.
So i must use bitcoin core? bitcoin daemon version?
It depends on what you need. Bitcore uses NodeJS so it may be good to use that if you plan on using NodeJS. It has additionally libraries for it that may add wallet support, but you will have to find them yourself.
Bitcoin Core has the wallet and node stuff build it. You can communicate with it through the JSON-RPC interface.
It all really depends on how you want to do it and which is most secure and convenient for you.