In Wordle, you have to guess a secret five-letter word. Letters of the guess that are in the secret word and in the correct place show up in a green box. Letters that are in the secret word but not in the correct place show up in a yellow box. And letters that are not in the secret word show up in a gray box.
In this puzzle, the goal is to find the final word that is entirely green boxes, but you can only see the letters in a gray box. That means any letter you see cannot be present in the final answer.
In particular, that means the fourth letter of the second word cannot be an "O" or "L," so there's only one letter it can be. That letter is therefore in the final answer, but it's not the fourth letter of the final answer.
The third letter of the fourth word also can't be "O," so there's only one letter it can be. This site might be helpful for finding word options: https://onelook.com/?w=PL%3FZ%3F&loc=scworef&scwo=1&sswo=1&ssbp=1
Since you know what letter comes third, you know the third letter of the fifth word, and you can use that to figure out the fourth letter of the fifth word. Remember that the letter "R" can't come fourth and be green!
To finish the puzzle, you'll need to figure out the third word. Be careful when looking through the options. The third word starts with a silent letter!