Fortilink VLAN' s

Hello together,

i am totally new in Forti-HW and just run in problems ;)

I have to use a Fortigate 40F with 7 FortiSwitch 124F.

I already created the VLANS (for each Switch 1 VLAN over 20 ports), I used the Fortilink-Feature to do this.

VLAN are configured as DHCP.

So far, so Good.

One Problem is, i cant reach the Gateway from any VLAN, as in the Picture shown. So how do i assign the Gateway-Adresses to the Switch?

This is the first question, i think there will be more as the projects goes on ;)

I appreciate your advices, Thank You