When someone tags you in an Instagram post, this is automatically added to your profile in the "Photos of You" tab.
To hide these posts from your profile, follow these steps:
- Get to the "Photos of You" tab in your profile
- Find the posts you'd like to remove from your profile
- Click the three dots in the upper right corner of your screen and click on "Hide Options"
- Here you can choose to "Hide from Profile" meaning you'll be able to show it again if you change your mind, or "Remove me from post" Which will also remove the tag and is not undoable

Please note that the posts themselves won't be removed from Instagram, they simply won't appear on your profile anymore.