How to delete message setting in order to receive message on Android ?

Hi, I'm in trouble.

I used to have a Google Pixcel 3 until couple of years ago. Since it will be not supported because of 5G,

I switched to Apple 11.

Last week, my iPhone was stolen, so, I restored my original phone number and started to use old Pixcel 3 for now.

The problem is that I can send message to the people who I used to use iMessage with cannot send me reply.

I was told to delete iMessage setting from Icloud. How can I do that ?

Since my stolen phone has been turned off, and ready to delete data.

I have my old, old iPhone5s in my I cloud fortunately, and barely working.

Can I do something with this ?

I am so bad about the technology. Please help !!