Hi  @katana85 

Please see my answers below:

Is the hardware that I selected are correct? The switch is right for the job required? As I mentioned it is my first time and I just want to confirm.

>>>The switch can do that, that the configuration will be more complicated than using a SDN compatible switch. I will recommend SG2210MP or SG2428P instead.

How can I configure the switch to work as I need? Should I do some configurations on the controller? network cable is enough to connect between them? Can I use SFP?

>>>You situation is same as this article:  How to configure Multi-Networks & Multi-SSIDs on Omada SDN Controller

Since I will be having 5 SSID's, Can I specify the encryption for example on SSID's 0 and 10 to be WPA3 and the reset of the SSID's WPA2? Perhaps someone phones do have WPA3 support.

>>>Yes

The print will be on VLAN ID 20, is it possible to connect to it from VLAN 0 and 10 and print? Note by default I will deny access from one VLAN to another except the printer if possible.

>>>Yes, you can refer to this link to configure mDNS. How to configure Multi-Networks & Multi-SSIDs on Omada SDN Controller

Is it possible to disable VPN connection for the clients?

>>>Yes, if you don't need VPN function, just not touch the VPN tabs.

The non smart switch should allow access to wired devices on VLAN 10, what should I do on the smart or the controller to do that?

>>> You can configure the uplink port on the smart switch into VLAN10, after that, all clients on the non smart switch should be in VLAN10,

The internet connectivity should be online 247. Suppose that I have two of the ER7212PC, is their a way to live backup the configuration from device A to B? and in the case of an issue, I can swap the first device with the second and connect the cable and works as it should?

>>>What you need is to subscribe two Internet service, and plug the two Internet service provider into one router, and configure link backup on the Omada router. You don't need to ER7212PC.

Note: ER7212PC can only manage up to 2 Omada switches and 10 Omada access points at most. If you are planning to manage more SDN devices, you may consider replacing the ER7212PC with one OC200 and one ER605.