To understand how an EA trades, you need to know at least some of the basics of forex trading.
But trust me, it’s better to stay with manual trading. There is no EA for sale that is profitable on the long run. You will be scammed, first by paying for an EA, second by losing money with it. The only ones that get rich are the creators and brokers.
My advice: start with learning about money management, support & resistance and trendlines. Don’t be fooled by people who claim to have a magical indicator. Indicators are always lagging and tell you what happened in the past. Your eyes and brain can see and interpret what happens real time.