Not able to upload media

Sound like the permission are wrong on your host .. i.e. wordpress cant make changes or add folders on the server.

see
https://codex.www.ads-software.com/Changing_File_Permissions

and
https://stackoverflow.com/questions/18352682/correct-file-permissions-for-wordpress

also you could try contacting your web host to see if they’ll let you know what permissions you need to set.