Hi @garak0140,
If you haven't already created your cloud dashboard, start there.
You can add your devices under Organization > Inventory or under Network-wide > Add devices once you have created a network for your remote offices.
You can then start the configuration of that network in your dashboard. When the devices are physically put in place and have a valid connection to the internet, they will automatically check-in to your cloud setup configuration and pull those configs down. Make sure your network is solid and running as designed before moving on to the site-to-site vpn setup.
See Meraki's documentation for more site-to-site vpn information. I think the documentation on their site can help you through most basic setup scenarios as long as you are familiar with networks in general.
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