To create a bootable macOS USB run the command below as mentioned on Apple Support site.

sudo /Applications/Install\ macOS\ Ventura.app/Contents/Resources/createinstallmedia --volume /Volumes/usb
Ready to start.
To continue we need to erase the volume at /Volumes/usb.
If you wish to continue type (Y) then press return: y
Erasing disk: 0%... 10%... 20%... 30%... 100%
Copying essential files...
Copying the macOS RecoveryOS...
Making disk bootable...
Copying to disk: 0%... 10%... 20%... 30%... 40%... 50%... 60%... 70%... 80%... 90%... 100%
Install media now available at "/Volumes/Install macOS Ventura"

The caveat here is that the Install macOS Ventura.app must be in the /Applications folder. If it's moved to any other directory and using that as the path the installation won't start. Running the above command should show Ready to start. message.

If you check the USB from Finder it will show only Install macOS Ventura.app file. But there are other files in it. The terminal output is shown below.

ls -la
total 3064
drwxrwxr-x  55 jsloop  staff     1938 Dec 21 12:32 .
drwxr-xr-x   5 root    wheel      160 Dec 21 12:32 ..
-rw-r--r--@  1 jsloop  staff     6148 Dec 21 12:32 .DS_Store
-rw-r--r--   1 jsloop  staff      361 Dec 21 11:33 .IAPhysicalMedia
drwx------   4 jsloop  staff      136 Dec 21 11:33 .Spotlight-V100
-rw-r--r--@  1 jsloop  staff  1400427 Oct 12 18:17 .VolumeIcon.icns
drwx------   5 jsloop  staff      170 Dec 21 12:32 .fseventsd
-rw-r--r--   1 jsloop  staff        0 Dec 21 11:33 .metadata_never_index
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j132ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j137ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j140aap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j140kap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j152fap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j160ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j174ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j185ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j185fap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j213ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j214ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j214kap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j215ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j223ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j230ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j230kap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j680ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-80958-022.dmg.j780ap.im4m
-rw-r--r--@  1 jsloop  staff     2801 Dec 21 11:39 097-80958-022.dmg.x86legacyap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j132ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j137ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j140aap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j140kap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j152fap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j160ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j174ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j185ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j185fap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j213ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j214ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j214kap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j215ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j223ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j230ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j230kap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j680ap.im4m
-rw-r--r--@  1 jsloop  staff     2800 Dec 21 11:39 097-81051-022.dmg.j780ap.im4m
-rw-r--r--@  1 jsloop  staff     2801 Dec 21 11:39 097-81051-022.dmg.x86legacyap.im4m
drwxr-xr-x@  4 jsloop  staff      136 Dec 21 11:39 BaseSystem
drwxr-xr-x@ 97 jsloop  staff     3298 Dec 21 11:39 Firmware
drwxr-xr-x   3 jsloop  staff      102 Nov 19 01:45 Install macOS Ventura.app
drwxr-xr-x@  3 jsloop  staff      102 Dec 21 11:39 Library
drwxr-xr-x@  3 jsloop  staff      102 Dec 21 11:39 System
drwxr-xr-x@  3 jsloop  staff      102 Dec 21 11:39 restore
drwxr-xr-x@  3 jsloop  staff      102 Dec 21 11:39 usr

To install from the USB, start the mac with USB inserted and press and hold the Option(Alt) key until the disk details are shown. Connect to internet so that firmware and other details can be obtained during installation. Click on the Install macOS Ventura option and proceed.