First of all, there are a few problems in defining this. Trying to play brz boom against a close opponent(similar skill level) going tool aggression, you will die. In such situation fast brz into military(cavalry is best) is necessary.
But let’s look at the case of brz vs brz play. You hit tool at 24-26 pop, click wall, make market+range/stable, click brz and build your walls. Make a note to try and be walled before 10:30 in team games. Scouts from home hit you at that time. If you think someone is likely to paint scouts, then you need to be walled before 10:00.
Let’s assume that is all good and you hit your brz before 13:00 behind walls(NOT houses!) You made 8-10 farms on the way up so now you rush your government center and two TCs on woodlines. Then you use all your extra wood on farms until you have 18 farms(21 for palmy, 15 for shang). This is what you need for villager production. If your opponent made two TCs as well(scout or check statistics for vil count) make one TC+farms, if he made only two TC make army with all extra resources from this point. Play carefully and you will catch up soon.
If he didn’t make government center he needs to break your wall and kill you (or your teammates) or he will lose. This is the most dangerous situation. You need to double wall and stop villager production from last TC, use that to make army. If he is any good, there will either be siege breaking your walls or he will kill your teammates so you will need army. Do not be afraid to sack vills for holding the wall. Hold it at all cost until you have enough army to fight and win. If he goes to your teammate you can help him, but at no point should you lose your army. Sometimes it is a better idea to your enemy at his home if it’s close when he goes after your teammate. He might pull back or you can kill a player. When the dust settles it is important your team has more eco and equal army. From this point forward it is just execution to win.
Regarding the build order:
5 to berry
6 make house -> scout (Look for wood then food then wallspots
7 berry
8-9 to wood
10 make house -> scout (make all houses from now on)
11-14 to wood -> make pit as soon as you can on good woodline(Food too if possible, priorise wood)
15-20 to a new food source, If you have food at your pit take two vills from wood and put on food,
20-25 to a new food source. If no food near pit, take two from wood.
Click tool
When first berries run out, transfer to gold/wood(Depending on unit you are planning to make)
Halfway up make barracks at a wallspot
Should have eco like this:
14 on food
6 on wood
(3 gold if cav) (9 wood if not)
2 scout
Now send 4 more vills to wallspots from the resource that is close and plentiful.
Queue one more vil from TC
Upon hitting tool click wall
Rush market+stable/range
Build walls as soon as able
Click brz
While on way to brz get woodcutting and start making farms.Transfer foodies to wood(new pit) when food runs out. If you are rich get domestication/gold mining and something to scout the enemies.
Aim for 250 wood in the bank, spend all extra on farms/ upgrades during age up. Queue some vils from TC while at it.
Hit brz
-> see start of post
Cavalry is usually the best choice for army. They can be made immediately, kill all tool units well with just one attack upgrade and use gold(cheapest resource). If you are not under pressure composite bowman is the strongest brz unit but is very slow to mass due to needing many buldings and upgrades. Chariot archer is somewhat in between. They don’t need that many upgrades but are the most expensive. These are the most common choices and in generic teamgames the best ones.