You'll need CRM Delete rights in order to follow the steps in this article
Step 1: Find Delete Option in Further Options
Firstly, navigate to the Report that you wish to delete from your CRM. You can delete Reports from both the My Reports and Shared Reports sections.
Once you've found the Report, click the three dots in the top right-hand corner and select 'Delete'.
Step 2: Confirm Delete
Finally, click 'Confirm' if you wish to delete the Report and then it'll be removed from the CRM.