The game can be played in any way convenient for you.
You can just guess by trying different options, or helping yourself by opening the letters. But the best option is to play Genshin Impact, in search of those shown in the picture. You have a photo, you have a game, start hunting! Find all the characters and have fun, because you will play two games at the same time) Perfect pastime.
You can call your friends into the game and compete with them who will be the first to guess a particular character, finding him in the game) Consider this a new look at Genshin Impact. You can spend a lot of time on some characters, but if you get tired, or cannot find it even with friends, you can help yourself by opening the letters, removing extra letters or skipping this level altogether.
I believe in you, and I will be glad to hear from you. If you go through everything, write down what you liked the game, and if you want new levels. Enjoy your game and meet at the Genshin Impact.