To share files internally or externally, you can use Onedrive.

To share it, do as following

Open Onedrive (for example from the Waffle icon)

Navigate to the file or folder you want to share

Tick the file (or folder) and click on "Share"

OR

Click on the Share icon next to the name of the file

A pop up will appear

With the default option,you can send directly enter the email adres ( external or internal), provide a message or copy the link to send it in another or using even outlook.

Click on Send to finalize

More…

If you want more control, click on the "anyone with the link can edit" option to have more choice

Sharing with code validation

Choose the sharing options
Select Specific People Chose or not Allow editing Select or not review mode only Then click Apply
Send the link
Enter the email addresses of the recipients Type an Optional message Click Send Note Only external recipients will receive a validation code. External people who have existing Microsoft account link to the used email won’t need to use the code procedure.
Recipient notification