Tashahhud is a special prayer that Muslims say when they are sitting down during their prayer. It's like a special conversation with God.
When you pray, you stand up and then you bow down, and then you stand up again. After you do this, you sit down and then say the tashahhud. It's a way to show God how thankful and grateful you are for all the things he has done for you.
During the tashahhud, you hold up your finger and say "There is no God but Allah, and Muhammad is his messenger." This means that you believe in only one God and that Muhammad is his messenger who showed people how to pray and be good Muslims.
Then you say some special words in Arabic that thank God and ask for his blessings, peace, and mercy. You also say special greetings to the Prophet Muhammad and his family.
After you say the tashahhud, you end your prayer by saying "Peace be upon you, and the mercy and blessings of Allah." This is like saying "I hope Allah blesses you and takes care of you" to everyone around you.
Overall, tashahhud is a special part of Muslim prayer where you can talk to God and show your gratitude and love for him.