How to access the files from the HDD disk

Hi I tried to use NextCloud on Raspberry Pi for a year.
Unfortunately, I do not have much time and energy to search for solutions for eternal problems with this system.
A week ago I did not have the Internet for a few days and NextCloud stopped working, does not synchronize files, the phone does not see the server, etc.
I have access to the admin and active SSH panel.
How do I download my files from the HDD disk where is my database? I would like to do it by connecting the drive to Mac / Windows.
I want to definitively remove NextCloud.