I bought Bitcoins from the ATM and it gave me a receipt with a QR code. and now after one year i wanted to scan it into my wallet, but ink on paper faded and it can`t be scaned..... so im wondering if i can enter the private key manualy by keyboard?
Your QR code contains your private key, but yes you can recover with the private key directly if the QR code is now physically damaged.
I do not see that option for blockchain.info (which you stated you are trying to use in your comment):
https://blockchain.info/wallet/import-wallet supports QR codes Bitcoin-Qt (wallet.dat) and blockchain.info (wallet.aes.json) files.
Try one these methods instead (or choose another wallet which you prefer):
No need to re-invent the wheel for importing or sweeping paper wallets for mobile wallets such as airBitz, Blockchain, and Mycelium. The Jaxx wallet also supports sweeping paper wallets under (Tools)->(Transfer Paper Wallet). These wallets should allow one to type a paper wallet's private keys if QR codes can't be scanned.