Three things. One will help the other with an Overall PLAN which is required.
1. Detail the requirements as you understand them
a. identify all user(s)/device(s) ( internal and external and admin)
b. identify all the traffic they need
2. You have a single WAN pppoe, so that is known................
Do you have any VPN to the Router, or doing any port forwarding?
If so ensure you detail it above in 1 a., b.
3. Draw a network diagram that shows the ports and subnets/vlans going out ports or WLANs
4. Read this article for vlans -->
viewtopic.php?t=143620
5. Create and post your config once done.
/export file=anynameyouwish (minus router serial number, any public WANIP information, or user name etc. )
6. In terms of firewall rules, stick to the defaults at least in the input chain for now. Keep chains together all input and all forward, order within chains is also important.
In the forward chain take the confusing default rule and remove it and then replace with three rules for now aka ready for future vlan usage.
From:
add action=drop chain=forward comment=\
"defconf: drop all from WAN not DSTNATed" connection-nat-state=!dstnat \
connection-state=new in-interface-list=WAN
TO:
add action=accept chain=forward comment="internet traffic" in-interface-list=LAN out-interface-list=WAN
add action=accept chain=forward comment="port forwarding" connection-nat-state=dstnat disabled=yes { enable it if required or later remove }
******************* --> Place any other needed traffic rules here, like vlan to vlan, shared printer etc..... <-- ***************************
add action=drop chain=forward comment="drop all else"
7. Before you start configuring anything, suggest take one port OFF the default bridge and we will set it up so you can access the config off the bridge, from a safe location.
/interface ethernet
set [ find default-name=ether5 ] name=OffBridge5
/ip address
add address=192.168.77.1/30 interface=OffBridge5 network=192.168.77.0
/interface list member
add interface=OffBridge5 list=LAN
With this in place, now plug your laptop into ether5 on the router. Change the IPV4 settings on the laptop to 192.168.77.2 and then use winbox entering usual username and password and you shouild have access to the config but off the bridge. This faciliates adding vlans to the bridge and going away from the default 192.168.88 subnet etc........... Also helpful when changing vlan-filtering to yes on the bridge.