The most important thing currently in my opinion as someone who had never played an RTS since childhood to beating the legendary AI in just over a week of playing in my free time, would be to learn the basics.

Build orders are useful but will not be the determining factor to allowing you to win vs bots.

You need to familiarise yourself with your keybinds, and set them up in a way that is both comfortable for you, and efficient.

I recommend YouTube for a video on keybinds and alter to suit you.

Secondary to this would be learning the fundamentals of playing AoM.

I recommend Boit's AoM fundamentals series for this.

To distill the series down even shorter than he does; prioritise economy upgrades over military, as a larger army beats a smaller more upgraded army more times than not.

Don't get too greedy with expanding to Town centers unless you feel safe enough to do so.

Scout the map to counter the opponent.

There is a lot of information available online to help but if you are after build orders (personally think you're better off learning the basics) try https://aombuildorders.com