Connect each switch with individual uplinks to bring them both online and ensure they can check in with the Meraki Dashboard.
Download the latest firmware build using the Firmware Upgrade Manager under Organization > Monitor > Firmware Upgrades, if they are not already set for this. This helps ensure each switch is running the same firmware build.
With all switches powered off and links disconnected, connect the switches together via stacking cables in a ring topology (as shown in the following image). To create a full ring, start by connecting switch 1/stack port 1 to switch 2/stack port 2, then switch 2/stack port 1 to switch 3/stack port 2 and so forth, with the bottom switch connecting to the top switch to complete the ring.
For DHCP handling, you would configure DHCP relays or DHCP servers on the Switch -> Routing & DHCP page in Dashboard. Keep in mind that both DHCP & L3 routing are configured on the switch stack, not the individual switches. You can see the stack setup & status on the Switch -> Switch stacks page. The default route would also be configured on this page at the bottom under "Static routes".
Meraki does not have a global VLAN definition like Cisco or other switches. If you configure a VLAN on any port on a switch (or any port in a stack), that VLAN is now in the list for the entire stack.
If ports on the second switch are missing the WiFi VLAN's, you can just edit the ports with AP's attached to the correct config. Meraki switches do use the same access/trunk setup as Cisco switches.