How to merge all the partitions to normal
To get the default partition layout you have to remove Apple_Boot, the empty container disk2, the almost empty container disk3, erase disk0s3-disk0s4 to free space and finally resize your main container.

Boot to you main system.

Open Terminal and enter:

diskutil list
diskutil ap list


to get the details.

Check your disk:

diskutil verifyDisk disk0
diskutil verifyVolume disk0s2


Remove all partitions and container except the main container:

diskutil eraseVolume "Free Space" Nil disk0s5
diskutil ap deleteContainer disk2
diskutil ap deleteContainer disk3
disktutil list #to get the new dev identifiers of the converted partitions
diskutil eraseVolume "Free Space" Nil disk0sY # Y probably one of [3-7]
diskutil eraseVolume "Free Space" Nil disk0sX # X probably one of [3-7]


Resize your main container:

diskutil ap resizeContainer disk0s2 0


Finally diskutil list should look more or less like this:

/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *251 GB    disk0
   1:                        EFI EFI                     314.6 MB  disk0s1
   2:                 Apple_APFS Container disk1         250.7 GB  disk0s2

/dev/disk1 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +250.7 GB   disk1
                                 Physical Store disk0s2
   1:                APFS Volume Macintosh HD            140 GB     disk1s1
   2:                APFS Volume Preboot                 21.3 MB    disk1s2
   3:                APFS Volume Recovery                509.8 MB   disk1s3
   4:                APFS Volume VM                      2.1 GB     disk1s4