You can get a link to photos and videos that are shared on Instagram. If the account that posted the content is set to private, any links you share can only be seen by followers of that account.

To get a link to a post:

1. Tap (iPhone) or (Android) above the post.
2. Tap Link.

To get a link to a post from the web:

1. Open your web browser.
2. Go to instagram.com/username. For example, if the username is "johnsmith," type in instagram.com/johnsmith as the URL.
3. Click the post you want to save and copy the link at the top of your browser.

Source: https://help.instagram.com/372819389498306