If you haven't already put the file you want to share into your OneDrive - continentaloffice.com folder.
Right click the file, choose OneDrive - continentaloffice.com > Share
You'll get this pop up
First thing is we want to set the sharing permissions. Click the "Anyone with the link can edit" and you'll get these choices
Anyone with the link - This means anyone who has the link can access it. So I set it to that and sent the link to Person1 who then forwarded the email to Person2 they could both access the file as they both have the link.
People in continentaloffice.com with the link - This only allows internal users with a continentaloffice.com email address to access the file.
People with existing access - provides a link that can be used by people who already have access to the file, folder, or list item. It does not change the permissions on the item. Use this if you just want to send a link to somebody who already has access.
Specific People - Only the specific people you list can access it.
Now as you choose the level of access, the options will change. If you do "anyone with the link" you can also choose to set a password as well as allow editing, or set an expiration (by default the longest we can share something with the anyone with the link option is 720 days). But if you choose "only people in continentaloffice.com or specific people your only choice is to allow editing.
Block Download - this option is only available if they are not allowed to edit the file. Then you can also further restrict by not letting them download it.
Once you have the desired sharing access chosen hit APPLY.
Now you can fill in an email to share it with, along with a brief message and hit send. Hit copy link to merely copy the link for pasting into another email or document, or click the Outlook button to have it start a new email with the link for you.