Sorry for the probable absurdity of the question but would it be possible to make a bridge trunk, for example, on port 3 and deploy some vlans ?
Don’t crucify me 
YES.
Maybe start with this: http://forum.mikrotik.com/t/using-routeros-to-vlan-your-network/126489/1
There are multiple solutions with Mikrotik. All VLANs could coexist as separate VLAN on the same bridge.
Using multiple bridges (even one per VLAN) used to be one of the older config methods to connect VLAN with non-VLAN interfaces
In a pure router setup, VLANs could be defined directly on the interfaces, if they are interface specific.
MT ROS is a combination of router and bridge/switch functionality.
Thanks for the advice.
I read it yesterday, but I have a confusion you can’t imagine.
I wanted to ask a question but I’m too confused to write it down.
I’ll sleep on it and then try to formulate it.
I hope to sleep on it is to not get into the loop of vlans in the bed.
Thank you, Alberto
I have a confusion you can’t imagine.
I know the feeling, digesting a lot of new concepts can give sleepless nights. Tackle the VLAN concept in MT just slice by slice. It’s hard for everyone, even experts in MT, as I see these discussions: http://forum.mikrotik.com/t/vlan-in-new-bridge-only-config/116768/1
Go for your case only, not all possible VLAN cases at once. How many separate L2 subnets do you have around this router? How many of those subnets are connected to multipe ethernet ports ? What ethernet ports have multiple separate L2 subnets ( e.g.carried in VLAN)
L2 connected VLAN on multiple ethernet ports need a bridge. The bridge handles multiple separate VLAN at once with the post ROS 6.41 VLAN filtering. The ethernet ports that carry some of those VLAN are slaves (ports) to that bridge. There are access ports (one untagged VLAN ), trunk ports (multiple tagged VLAN) and hybrid ports (multiple tagged + one untagged VLAN) possible.
With bridge VLAN filtering off (disabled) the bridge will pass all bridge connected VLAN to all its ports untouched. (Like a dumb switch)
Suggest one bridge, rest vlans… not at all what you have.