If you want to allow visitors to access the course, go to the Participants addition methods, i.e. click on Participants on the left navigation, then on he right side click on the gearwheel and press Enrolment methods.
Click the Guest access eye icon at the right side so that the line across the eye is removed, the login method is now enabled.
If the Guest access login method is not visible, select it from the Add method menu.
Click the gearwheel on the Guest access line at the right side to configure the settings.
Select Yes to Allow guest access menu. You can set the password by clicking the "Click to enter text" field. Save your changes and guests will have access to your course.
If you set a password, only those guests who know the password will have access to your course. You can change your password at any time.
If you do not set a password for guests, everyone will have access to your course in the guest role.
A guest can view the course material and have access to the materials, but the guest cannot participate in activities such as discussions, exams, etc.