Basic understanding of coding

Why we have to code certain strategy as

  1. BUY:(Strategy)

2 SELL(Strategy) format.

Does it automatically execute trading once met with strategy. Suppose I want to scan simple buy set up then what I have to do?

Defining the Buy or Sell Condition is very important and common for all no matter which ever coding language you use to code your strategy, with Buy or sell functions system will identify and understands it