I've got some big lacks of skills in my military strategy. Help me find the problem

Me and my lads are back with the AoE 2 Action and I realise I'm pretty Shit. Important we always play in teams at least I do.

First of all to my major problem. I can never decide for a Civ. I try out these and realise that I'm never comfortable with any of these. Also I don't got the DLCs so less civs

So in Dark Age I'm doing a good job. Slaughter Sheeps. Starring on wood. Farming at the end there is my way to the feudal age. Pretty basic.

There is where I fuck up I think. I send like 3-4 to gold before I start feudal age and then the basics again. Market then Kartography and so on. Then the blacksmith. Then building at least defence with walls and towers. I also build barracks and archery and stables. But I don't produce any.

So I boost my economy. Normally it's 5 on rock, 5-8 on gold (depends), A lot of farms like 10-15. And then like 15 woodmen. Then I start to develop castle age.

So that's where me and my lads start the first siege on somebody and I really don't have a lot of troops in comparison to my lads. So I normally make some Knights or camel fighters (depends on my special unit). So I build up my Shit and I contribute not much to the battles. Maybe as the secret little backup. I normally don't build any seige weapons in Castle age. So what's the best stategy as I hit castle age? Like a general strategy. Is there a problem with my feudal age? I've got no clue and the tutorials on yt are too advanced and specific. Any good civs (except Britons or major one. Basically they are already taken)

Thanks