I am a developer. these days we are going to jump into Crypto well. So i have read lots of blog online how Crypto currencies works. But i am little confused for the private key.
1) Where it is stored in decentralised ledger.
2) How it is validated while sending payment to any other key.
guys please help me to under the concept of private key.
I can assume you are coming from JavaScript background, according to text in profile. In this case you probably find helpful the "crypto" library from NodeJS
https://nodejs.org/api/crypto.html , especially the ECDH part
https://nodejs.org/api/crypto.html#crypto_class_ecdhIt also has some examples and explanations.