I’ve just discovered this daily crossword page. The crosswords are free but it plays a 10 second advert before you can start. You fill in your answers online and it automatically highlights the next relevant clue. Clever. Also there is a timer so you could set up a crossword race among friends!
If you prefer a quick crossword or a cryptic crossword those options can be found here: https://www.crosswordsolver.org/crossword-puzzles/