RouterOS is so versatile that there isn’t a one-for-everybody way of doing things. ROS has a steep learning curve, but when you get over the initial steep part, it becomes all pleasure.
My advice: start from foundations. On drawing board. First plan the physical connections (wireless as well). On top of physical connections come VLANs. On top of that comes everything else. BTW, this has to be done with any equipment vendor, not just Mikrotik.
Worth to read: a very good tutorial on VLANs in ROS and explanation about different bridge functions (you’ll run into dilemma why the heck bridge is treated in different ways).
Another advice: keep default firewall setup intact as far as it goes. It is pretty solid to start with, you’ll only have to make minor adjustments to make it fit your VLAN layout.