To disable the local search box on the homepage:
- Go to the admin edit page of your active theme under Design > Themes
- Select source
_pages/home
- Click the Local Search Component
- Set Hide Location Search to Enabled
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You'll also need to disable the local search validation for the checkout page so your users can place an order without the delivery area validation.
- Go to System > Settings > Order & Reservation
- Under the Order tab, set Require Location To Order to NO