There are various means for excluding files or locations from backup. Only the first method will actually delete all file versions from the backup, the latter methods will only exclude newer versions from being added.

Method 1:

Right click a file/folder → Point to Genie TimelineRemove from backup. This will also delete all version of the file in backup.

Method 2:

Drag drop files to No-Backup Zone located on the Desktop.

Method 3:

Modify data selections, and add file filtering options, or customize smart selections.

Method 4:

Auto-Exclude to exclude full file and folder paths.