Hi anishgowda21,
We appreciate you reaching out to us.
You are correct. The only recommended way to import and export keychain items is to use Keychain Access on a Mac.
To import keychain items, please follow the steps below.
- "In the Keychain Access app
on your Mac, choose File > Import Items. - Navigate to the keychain items file you want to import and select it.
- In the Destination Keychain pop-up menu, choose the keychain you want to import to, then click Open."
You can use the article below as a reference.
Import and export keychain items using Keychain Access on Mac - Apple Support
After importing your passwords, you can then try the rest of the steps in the article below to make your passkeys and passwords available on all your devices with iPhone and iCloud Keychain
Make your passkeys and passwords available on all your devices with iPhone and iCloud Keychain - Apple Support
You can leave feedback about Apple products here: Product Feedback - Apple
Take care!