You may need to use EasyUEFI to change boot loader Item order and I think you may need to run terminal
and input diskutil list and take look about some partition information if you got the single hard drive and you may
see the terminal output information such like this:
/dev/disk0 (internal, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *xxx GB disk0
1: EFI EFI 209.7MB disk0s1. (it may not exist)
2: Microsoft Basic Data xxx GB disk0s2
3: Apple_HFS MacintoshHD xxx GB disk0s3
if you can see the Item 0 as GUID_partition scheme but not had EFI you may need to recreate it use some tools
such like Disk Genius or paragon Partition manager or Aomei partition assistant to create new EFI partition
your Mac looks like haven't any EFI partition probably
I think you may need to recreate one but if you want to change some clover preference you can edit it in your Mac OS Root directory:
get in EFI/Clover/Config.plist to Change all value use Text editor or property list editor.
hope that I can help you :D