do you buy at resistance or support?

A resistance level usually prevents price from moving upwards, so I always sell at the resistance, but I wait to see a bearish engulfing confirmation candlestick pattern before i sell.

I don't rush to sell at a resistance because resistance can suddenly fail and turn to support . I wait to see how price reacts to the resistance line before taking action. I wait to see an opposite bearish 5-minute candle before i sell.

The lowest risk entry is to wait for resistance to become support before buying. However, this may not always happen as sometimes price could just push through resistance without returning to retest it.

I wait for price to reject at a support level and begin an upward movement before I buy

The support zone is a price level where buyers usually come in. That level prevents price from falling further.

Resistance zone is a price level where sellers usually come in . That level prevents price from rising further.

Personally, I love seeing multiple candle rejections at a particular support level before buying, the rejections at that level signifies that buyers are strong at that level. The same applies for the resistance level.