How do you link your Facebook account to your Instagram account?

Linking your Facebook account to your Instagram account on Instagram is mandatory.
Follow these steps to link your Facebook account to your Instagram account on Instagram:

1. Log in to your Instagram account.
2. Click your profile icon.
3. Click Settings.
4. Click the Accounts Center on the left-hand side.
5. Click Add accounts.
6. You will be directed to the Facebook login screen. Enter your Facebook account login details and click Log In.
7. Click Continue.
8. Click Add.

With this, you have now linked your Facebook account to your Instagram account.