Open the presentation. On the top line, select Access.
Then, in the menu that appears, you can set the type of access to the presentation: with limited (Private) or public access (Available to other companies).
In the second mode, you can adjust the level of access for third parties. For example, you can specify a list of companies or employees who will have access to the presentation. You can also allow/disallow the creation of links to the presentation to other users within your company.