Do I have to upgrade to be able to set times and repeating events?
Although Todoist Premium offers over 20 awesome features, setting times and recurring tasks does not require an upgrade - both are available for free.
To set a time for a task, type "today at 2pm" or "Fri at 13:40" within the due date field. To make a task recurring, type "every day" or "ev Fri at 2pm" or "ev 20 days". For a full list of supported recurring date formats, please refer to this page: https://next.todoist.com/Help/timeInsert