- Click Settings in the Left Sidebar.
The screen shown below is the Settings tab.
- Click the BASIC LMS SETTINGS tile.
You should see a screen as shown below. Scroll down to 'Logo Settings'. 
- Click Change to add/change your logo
- When done, click Save.
From here you can add your company logo to:
- The website header
- LMS Login page
- The course completion certificate, and
- The website favicon