WhatsApp Cloud API Phone Number Can be Used by Mobile WhatsAPP or Business App?

You can't use the same phone number for WhatsApp Cloud API & Mobile App.
If your phone number is already registered with Mobile App, before connecting to WhatsApp Cloud API, you must need to disconnect from Mobile App.
WhatsApp Cloud API & Business App are also different. You can't also use same number for Cloud API & Business App.

So as you can't use the same phone number for Cloud API & Mobile App, you can't reply message from your mobile. You need to use Cloud API to send or receive message. BotSailor has this both option to send & receive message for WhatsApp Cloud API Phone Number.

If still you have any doubt, please feel free to ask here in comment section.

Thanks

So for botsailor
Is this cloud api or premise api

Please tell more detail about this different

It's Cloud API.

Cloud API where Facebook hosted their all resource for API call. Where on-premise was old features which is complex & neee to have many setup in server level. You will find complete docs here https://developers.facebook.com/docs/whatsapp/cloud-api/overview/

And here you will find the way to migrate your existing WhatsApp account to Cloud API https://botsailor.com/blog/how-to-migrate-your-existing-whatsapp-account-to-whatsapp-cloud-api