Actually, writing a letter is very simple. Write the title first, Dad, Grandpa or Grandma, and start a new line. This is the text. You can write out your thoughts and make things clear. For example, introduce yourself. Everything goes well in work, study and life, so that parents and grandparents can rest assured, and then pay attention to the physical condition, diet and daily life of the old people. Take care of yourself. You can also introduce local anecdotes, customs and so on. Finally, it is the end. You should start a new line and write some words of blessing. Here is your signature and date of writing.
Buy an envelope, put enough stamps on it and send it in the mailbox.