Please tell us what model of MikroTik router you have, as the configuration may vary somewhat depending on the mode the interfaces operate in. You may also want to post your "/interface export hide-sensitive" output and I am sure we can give more direct guidance. I have several SSIDs isolated to various VLANs and use a MikroTik router to secure/route between them and provide Internet access, it isn't that difficult but the way you add the VLAN interface/IP addresses may change a bit depending on the model you have (e.g. switch chip or not).