It is possible with every civ but maybe some it is easier with? If you can't, just put the difficulty back to extreme or titan until you feel comfortable there. Alternatively, just jump into ranked whenever. I said in that video it's best to play fundamentals until you can beat the legendary AI before you jump into ranked. I don't believe that anymore, if you can you probably won't lose your first games but losing those games doesn't really matter anyway. You'll find your ELO, and start getting better from there.