New Player - What I can do better and some feedback

I am having a Blast playing AO3 with my friends and although I feel I am learning quickly, I want to get better and have some feedback on what I can improve, specially with military units

I started playing first with Portugal. With them I understand that their main strenght is to grow the economy, enjoy the free urban centers and that the backbone of their army is Skirms+Dragoons+Art. But I feel so weak with them compared to German or France, I feel get stomped on early, mid and late game fights. Now I put them on reserve to play onwater maps only (which my friends dont like playing) to water boom

France...it was amazing the first games. I literally searched for "best treaty civ" and found them. And although I won most games, I did also lose sometime. What is the best military strategy here? Always go for Cuirrasier spam with Skirms and Art? Or Musks and Art? Or both Musks and Skirms? Should I ever use Goons here? Should I use trample?

And finally German. After my friend asked me to let him play France against me, I took Germany cause I saw that War Wagons countered Cuirs, lol. It has been by far my strongest early game, and as our treaty is only 10 min, I can get some good rushes ready at 10 min with my Uhlans. But what army do I use on late game? Spam Wagons? Mix Doppels and Skirms? Only one of those, based on the enemy army? I also honestly feel that my wagons burns faster to my Chinese-friend flamethrowers because it is made of wood (jk by how I deal with a soam of those???)

Also if it is not too much, what are the best decks for those 3 civs?

When Musks or Skirms are better?

How far I should go with tech upgrades on my market, mills and proprieties?

I am doing wrong on using my factories to resources instead of heavy cannons?

Anr finally, are the Xbox PC and Steam version the same or are they different? One can play with the other? Can I access my progress if I switch from on to the other?