Based on diagram, the solution you are looking for is called “Router on a stick”, I did provide a link for this in my previous post.
What I don’t see, and you might have removed this info before pasting, is the vlan-id’s in below:
/interface vlan
add name=10.10.10.1 interface=ether9 disabled=no
add name=10.10.20.1 interface=ether9 disabled=no
…
If there are no firewall rules blocking comms between these vlans and WAN port, it should work by default, i.e. The Mikrotik router will create a “Direct Attached Connected” route for each Vlan, then you will have a default gateway route via the WAN interface, either created dynamically or statically, depending on your setup and the various vlan’s will route via this interface to internet