how can remove icloud

You will need to contact the previous owner and request that they remove the phone from their account (They can do it from a browser) or if they provide the password, then you can do it (but they probably won't give out that info).

See here:

Activation Lock for iPhone and iPad – Apple Support (AU)

umair6 wrote:

how can remove icloud

iphone lock to owner

please remove icloud

https://discussions.apple.com/content/attachment/e4e4ff10-467f-4b0a-9dfc-3f7fdac94932

remove icloud - Apple Community

the device is useless without the original owners information.

Recycle the device nothing you can do.