i tried to get the private keys for the defi address i did not find it , only public key .
You will not get private keys, but a 12-word recovery phrase/Secret Private Key Recovery Phrase.
See:
https://support.blockchain.com/hc/en-us/articles/4417080393108-How-to-make-a-wallet-backup-https://support.blockchain.com/hc/en-us/articles/4417077967508-Your-Wallet-Its-Master-Seed-How-do-they-work-is this type of false marketing to give fake sense of security ? since i got confused by their articles . my question if you put btc in regular blockchain wallet without moving it to Defi address your are way less secured ? by Blockchain.com Account they mean verified account only or unverified too ?
Yes, it is less secure, in fact, you technically do not own the bitcoin since you are giving the "control" to them. Both apply for verified and unverified.
But I won't call them giving a false sense of security, they just offering a custodial service.
can you still have access to DeFi wallet balance with 12-word Recovery Phrase only ? and how you will be able to complete recovery into other wallet without a file ?
Yes, Blockchain dot com generates an industry-standard 12-word recovery phrase. As long as you keep the phrase secure, you able to simply recover it by the phrases on many wallets. The compatibility is ensured since it is being used widely.