does deleting recents remove items from my desktop

Oh dear, the thing to remember is Recents is a virtual folder it doesn't exist. It is just an alias to where your files are actually stored.

So if you delete items, from Recents it is actually deleting the items from where they are actually stored.

For example create a test document in word or text edit and store it in your documents folder. Open a Finder window

select Recents and highlight your new document, (if you have View> Show View Options> Show Path Bar activated

then you will see the path to where the document is stored) move the new document to the Trash and then empty the Trash you will notice that it has disappeared from the Documents folder.

As for restoring those items you have lost then it is highly unlikely you will be able to since it has been a few weeks since you trashed them. When items are trashed the system sees them as being available to be overwritten, so the more times you use the Mac the less chance of the files being recovered. Thats why you have been making backups on regular basis, isn't that correct.

I agree with Eau Rouge.

You shouldn't clear caches and such to clean or speed up your mac:

• the system clears caches itself on a daily weekly monthly basis
• caches are used to speed up things, not slow down
• you can "force" clearing some caches by restarting in the safe mode, login, the restart normal.
• clearing caches does not free up space for you: they are refilled again.

if you have TimeMachine, you can find the lost files again if necessary: go to the time just before you did the stupid cleaning.