In order to accept late Homework submissions on Canvas, make sure to use the Due Date and Availability settings when creating your assignments (you can also edit this setting after creating the assignment by clicking on the Edit option located in the vertical dots button and then selecting the More Options button on the following window, pictured below).

Edit Button

More Options

Due Date Settings

Set the Assign > Available Until to a later date/time than the Assign > Due

This will make your assignment available to students within the dates listed in the "Available from" and "Until" fields, and mark any assignment submitted after the Due Date as Late.
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Late submission penalties on Canvas can be configured in the Gradebook Settings section of the Grades area of your course by selecting the Late Policies option. This documentation from Canvas will walk you through the steps to set up the Late Policy for your class: https://community.canvaslms.com/t5/Instructor-Guide/How-do-I-apply-a-Late-Submission-policy-in-the-Gradebook/ta-p/965