How to send a text message to the elderly to register for WeChat?

Can't register for WeChat. Registering WeChat is a function of smart phones. Old phones don't support using WeChat, so old phones can't register WeChat, but you can register WeChat on another smart phone with your old phone number. When registering WeChat, send the verification code to the old mobile phone number, and enter the verification code on the smart phone to register successfully.