Moving WhatsApp to new phone without changing number

Question

Not sure if this has been asked before. I would like to move my WhatsApp installation and chats to my new phone and I would like to keep the same number associated with it, but I don't want to move the SIM with the old number into the new phone.

Everything I have read online about moving WhatsApp to new phone seems to apply only to one of two options, taking the old SIM into the new phone, or changing the number on the account to match the SIM in the new phone.

I know this is possible because I have seen French people using WhatsApp with their old French number from years back, but when I call them on their local number, that rings the phone on which the installation sits (not dual SIM)

Thanks