The files on your OneDrive are private until you share them. Remember that when you share folders with Edit permissions, people you share with can add the shared folders to their own OneDrive. This lets them keep the folder alongside their own folders and items, easily move items between folders, and more easily work on it offline. Any updates they make sync with the shared folder, so everyone with access to the folder is up to date.

Share with "Copy link" ( excellent option to send large attachments )

Choose this option to share items with many people you might not even know personally. For example, you can use these links to post to Facebook, Twitter, or LinkedIn or share in an email or message. Anyone who gets the link can view or edit the item, depending on the permission you set. Users with the link cannot upload new items. If the sharing link points to a folder, you may be required to sign in with a Microsoft account. Don't have one?

1. Go to the OneDrive website and sign in

2. Pick the files or folders you want to share by selecting its circle icon.
   • If you're using List view, select the circle on the left side of the item. You can also pick multiple items to share them together.
   • If you're using Tiles view, select the circle in the top right corner of the item. You can also pick multiple items to share them together.
3. Select Share   At the top of the page. 

Notes: 

4. Select Copy Link 

5. To change the link permissions, select settings:
6. Select one of the Share options
   • Anyone gives access to anyone who receives this link, whether they receive it directly from you or forwarded from someone else. This may include people outside of your organization.
   • People you choose will allow you to specify any email address. A Microsoft account is not required. It will use a code to verify the email address
7. select Apply. 
8. Select Copy and then select Send.
9. Paste the link and send it to your recipient.

Reference file