Email on iPad is going to the Junk mail folder

Try this:

Open the Junk folder in your Mail App on your iPad.

Tap on "Edit" in the right corner above

Select the Mail you want to keep from going into the Junk folder

Tap on “Mark” at the bottom-left corner of the screen

Then choose “Mark as Not Junk”

iOS/iPadOS15 doesn’t have an obvious method of marking an email as “not junk”.

Instead, if Mail is being incorrectly routed to your Junk folder, simply move the email message to your inbox. In this way your Mail App can learn that messages incorrectly categorised as Junk should instead be delivered to your inbox.