Change 2FA to send SMS
How can I change Apple ID two-factor authentication to send SMS to verified phone number?
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You can't change it to send only SMS but you can set up one or more trusted phone numbers as described in the "Trusted phone number" section of Two-factor authentication for Apple ID - Apple Support
You can then do the following as described in that same article:
If you're signing in and don’t have a trusted device handy that can display verification codes, you can have a code sent to your trusted phone number via text message or an automated phone call instead. Click Didn't Get a Code on the sign in screen and choose to send a code to your trusted phone number