How to delete downloaded files on Android TV I have a Sony Bravia TV with Android.

When trying to install a new app from the Play store it says I have to free up some space, as my storage is full.
When checking storage in the settings, it says the cca 5.5GB are in the Downloads folder.
But I have no option to delete it, as there is nothing like a file manager.
I also cannot download any file manager, or cleaner etc. as it won't install anything, cause the storage is full.
Any ideas how to solve this?
Although there seemed to be enough space (0.9GB) to install a small file manager app (about 30MB), I had to:
- clear caches from several apps
- deleting stored data from several apps
- uninstall some default app updates
After that I got about 1.6GB of free space, and just then it allowed me to install a File manager, where I was able to browse to the Download folder and remove unnecessary data.

I don't think this is a real solution, there must be another way, but this was the way that worked for me.