SEVERAL WAYS TO DO IT:
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* by using regex in the suitable Laravel Controller:

'phone' => 'required|regex:/(01)[0-9]{9}/' => ( add 'required' only if the field is required, else delete it!)
OR smthin like dis
'phone_number' => 'required|regex:/^([0-9\s\-\+\(\)]*)$/|min:10'
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* use this library: https://github.com/propaganistas/laravel-phone
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* use this in the corresponding laravel Controller:

 'phone' => 'required | numeric | digits:10 | starts_with: 6,7,8,9'
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* You can use a service like Nexmo or Twilio if you need to properly validate phone numbers.