Each unit that uses a SharePoint site has a Site Administrator (often called a site admin) and this individual is responsible for granting and revoking access. You may have a different level of access to your SharePoint site than others in your department, and your site administrator will be able to tell you what you have access to.
After you get confirmation from your site admin that you have access, they will send a link to your site. Please bookmark this, and consider making it your homepage.
