Delete & Purge
Remove files with filters, or remove a whole folder in one go.
Delete and Purge both remove data from a remote.
Delete removes files, and only files: it goes through the folder, removes every file that matches the filters, and leaves the folders themselves in place.
Purge removes a folder entirely, in one operation. It's the faster option if you're looking to delete everything.
Remember
Google Drive and a few other providers move deleted files to their trash first. Most do not.
Check the path twice, and use Delete's dry run when in doubt. If it already went wrong, read Deleted files by mistake.
Delete
If you want some of the files.
Open the toolbar and type delete. The window has one field, "Path", the folder to delete from. Type it or pick it with the folder picker.

Filters are what make Delete precise. You can hover over all of them to get an explanation.
For example:
max_agelimits the deletion to files newer than a durationmin_ageto files older than one, which is how you clear out everything older than thirty daysexcludeprotects every file matching a patternincluderestricts the deletion to matching files.
With a filter set, everything else under the path is left alone.
Purge
If you want the whole folder and everything inside.
Open the toolbar and type purge. Select a folder, set any flags in the Config section if needed, and start the purge!

Cron would make this a monthly clean-up, say for a folder that collects exports.
For info on the CLI versions of the commands (rclone delete, rclone purge), see the CLI docs
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