How Connect my 4 building with comcast ethernet

Distances between buildings, is the question dealing with each building getting their own Comcast connection using the firewall in each to establish a VPN among the other firewalls.
That might be a design that Comcast implements in the link.

Not clear what your two domain reference implies. Is that a local ad login domain, or you have two sites externally accessible.

Each building has a comcast fiber optic conexion I don't need a VPN because is a private conexion, about the domains is because I need configure 2 domain through the buildings

config gateway, DNS and default route for each network to your internet router.  

building 1 - 10.1.1.x network.  internet router .1
building 2 -1 0.1.2.x network . set default GW to 10.1.2.1
in the vlan 2, set route 0.0.0.0 0.0.0.0 to 10.1.1.1

make sure there is route between vlan 1 and 2.
make sure you allow vlan 2 network in firewall.

When you said internet router you mean Comcast Box? because I don't have access to Comcast Box Just them can Management , the configuration 10.1.1.x and gateway  i did that in my firewall, when you mentioned vlan 2 i need to create that vlan or comcast did?

You have two separate AD domains?
You can have each on their own segment with the routers separating the per domain traffic, while routing all other traffic through to the comcast box which presumably nats.  the issue with the comcast box deals with whether they are natting all your IP segments, or they have a specific one that

Internet <=> comcast box <=> your internal router <=> your other routers/connections

Your internal router will be getting a public IP and natting everything else behind it.

Yes I have 2 Separate AD Domains, I'm pretty confused about how to actually set up the EVPL really need help in that part

Do the domain hosts cross boundaries? Is establishing a trust between the two domains an option or are the two have to function as two separate entities?

Like Separates entities

the two have their own existing network, what equipment do you have?
How many routers do you have?

Right now I just have a Firewall in the main office but the firewall I can routing, but right now is not really important the 2 domains, the important part is how connect my other 3 building through EVPL

Lets try it this way, each building presumably has their own currently existing network
systems and switches. and has its own segment that is unique i.e. does not overlap with any of your other buildings/locations.
The fiber P-to-P. Does it terminate on a router?

Building A <=> router <=> Comcast Feed
Building B <=> router<=> Comcast Feed
Building C <=> router <=> Comcast Feed
Building D <=> router <=> Comcast Feed

You might want to setup dynamic routing (ospf) while might complicate some configuration on the front end, would simplify them down the line, i.e. you need to expand one location by adding another segment, with static routs, you would need to go and update the other routers one at a time about the new network.
With dynamic routing, you add the new segment to the advertised block on the router and you are pretty much done as the change will propagate.

If my guesstimate of your setup is incorrect, please post a topology.

The AD will deal with the DNS servers available to the location. So if building A and Building C have each separate domains, each will have a set of DNS servers that will point to the DCs responsible for it.

The Fiber is Point -to-Multipoint I think is something like

Comcast Switch -> Building A <=> router <=> Building B
Comcast Switch -> Building A <=> router <=> Building C
Comcast Switch -> Building A <=> router <=> Building D

for this kind of configuration I need router in each building? or router in the Building A and switch building B,C,D?