Short Answer 
To check someone’s account creation date on Telegram, first open the app and log in. Then, find the contact in the Contacts section, tap on their name to access their chat page, and click their profile picture to view their account join date.
Step 1: Open the Telegram App
Begin by launching the Telegram app on your smartphone or device. Make sure you are logged into your account to access the full features of the application. This is essential for navigating through contacts and checking profiles.
Step 2: Find the Contact
Navigate to the Contacts section within the app to locate the individual whose account creation date you want to verify. You can easily search for them by typing their name in the search bar if you have many contacts. Once found, tap on their name to proceed to their chat page.
Step 3: Check Their Profile Information
On the chat page, tap on the profile picture of the contact at the top. This will direct you to their profile page, where you should see the date they joined Telegram. This date is a good indicator of when their account was created, although it may not be exact if they have chosen to modify their privacy settings.