Click on the Admin Panel button.
Click on "Events" in the admin panel. Then, click the three dots next to the event you want to invite people to, and select "Invite."
You will be redirected to the Invite Members Dashboard page, click the Invite button.
You can invite all community members, or invite specific members. To invite specific members, search for the people you want to invite and tick the corresponding checkboxes. Then, click the invite selected button.
Here is a video explaining the whole process