can I use same wallet/private keys twice can i use the seed words of my online blockchain.info wallet on a trezor so i create a trezor wallet which has the same private keys as my blockchain.info wallet?And in the future i will only use my trezor wallet for transactions: I will let the blockchain.info unused.
Yes, both Blockchain and Trezor use BIP 39 standard seeds to generate the keys. Keep in mind that if you eventually stop using blockchain, it will still have access to all private keys used on the Trezor still, so it must remain secured, you can't just forget about it.