A candlestick shows four numbers for a period: open, high, low, close. Everything else, including every pattern name you have heard, is an interpretation of where those four numbers sit relative to each other and to the candles around them. Learn to read the four numbers and the names take care of themselves.
The four that matter
1. The engulfing candle
A candle whose body completely covers the previous candle's body in the opposite direction. After a decline, a bullish engulfing candle says buyers absorbed all of the previous session's selling and then some. It is only meaningful after a move, at a level that matters.
2. The pin bar (hammer and shooting star)
A small body with a long wick on one side. The wick is the story: price went there and was rejected. A hammer at support after a decline, or a shooting star at resistance after a rally, is a rejection of the level.
3. The inside bar
A candle whose entire range sits inside the previous candle's range. It is a pause. Traded as a breakout of the outer candle's high or low, it is one of the few patterns that gives a mechanical entry and stop.
4. The doji
Open and close nearly equal. Indecision. On its own it means little; after a long run, at a key level, it is the first sign the move is tiring.
The ones you can ignore
Three white soldiers, abandoned baby, evening star and the rest of the Japanese menagerie are mostly combinations of the four above. If you can read an engulfing candle and a pin bar, you can read all of them without memorising names.
Location beats pattern
The same hammer means nothing in the middle of a range and a great deal at a level that has held three times. Mark the levels first, then look for the candle. Never the other way round.