To share a document stored in OneDrive, first, make sure that the file has synced to the cloud. Then, right-click the document or folder you want to share and click the Share button next to the blue cloud, indicated by the screenshot below:
A new window will appear offering you a few options. Firstly, you can choose who you are sharing the file with. If you click the People you specify can edit button you will have a few more options to choose from. You can choose for anyone with the link to have access, only people within CIM with the link, people with existing access or specific people. Additionally, you can choose whether you want to allow editing rights, or whether you just want people to be able to view/read the document.
If you choose Anyone with the link, you can specify a few additional options, like giving a link expiration date (maximum 30 days) and setting a password to access the document. Please note, this doesn't apply a password to the file itself, it is just applying a password to the link, meaning someone would be able to view/edit the document in online mode if they were given the password.
Back on the main screen, you can type the email address of the person you are sharing the document with at the top, and then apply a message underneath. Once you click Send, this will automatically generate an email to the address/es you specified for permanent access to the document. If you just want to generate a sharing link, click the Copy Link button at the bottom of the window.
To view current permissions on a document/folder, click the 3 dots in the top right hand corner and choose Manage Access. This will showcase any permissions on the document, as well as links that have been generated with their levels of permission.