In the "Learners" tab
Search for the learner (filter boxes top or bottom) then tick the box at the left hand side of the name. Click on the blue button at the bottom left hand side of the screen.
Select "Enrol on E-Learning"
Select the courses required (you can add more than one at a time and you can search using the filter boxes) then "Preview"
Check the courses then select "Confirm & Enrol"