Does this mean that you copied the ISO file onto the device as suggested? Could you please show the exact command you used when doing that?

Did you try booting in legacy mode as well as UEFI, and in both cases the console display stayed off?

It is quite peculiar (and unusual) that your system has such a hard time booting. You never told which CPU it is. And the machine assembly as a whole, is that a certain "brand" or is it your own assembly? What's the brand of the USB stick?

[g4sra@localhost:OS]$ sudo dmesg

[13934.095824] usb 1-3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[13934.095826] usb 1-3: Product: TransMemory
[13934.095829] usb 1-3: Manufacturer: TOSHIBA
[13934.095831] usb 1-3: SerialNumber: C6EEBF9D8207CDB11D4F171F
[13934.119872] usb-storage 1-3:1.0: USB Mass Storage device detected
[13934.120010] scsi host8: usb-storage 1-3:1.0
[13934.120319] usbcore: registered new interface driver usb-storage
[13934.123274] usbcore: registered new interface driver uas
[13935.159151] scsi 8:0:0:0: Direct-Access     TOSHIBA  TransMemory      1.00 PQ: 0 ANSI: 4
[13935.159600] sd 8:0:0:0: Attached scsi generic sg4 type 0
[13935.159809] sd 8:0:0:0: [sdd] 15155200 512-byte logical blocks: (7.76 GB/7.23 GiB)
[13935.159996] sd 8:0:0:0: [sdd] Write Protect is off

[g4sra@localhost:OS]$ ls -l ~/ISO/Devuan/Daedalus/devuan_daedalus_5.0.1_amd64_netinstall.iso
-rw-rw-r-- 1 g4sra g4sra 501022720 Dec 27  2024 /home/g4sra/ISO/Devuan/Daedalus/devuan_daedalus_5.0.1_amd64_netinstall.iso

[g4sra@localhost:OS]$ sudo cp /home/g4sra/ISO/Devuan/Daedalus/devuan_daedalus_5.0.1_amd64_netinstall.iso  /dev/sdd

What commands did you actually enter ?
What was the result of those commands ?

How did you reboot your PC ?
What boot options did you select ?
What did the PC report ?

I suggest you try again, this time making *exact* notes most of which you can cut and paste, then after rebooting post them here on the forum.

So I mount ISO and then use general path instead of pointing on every directory of it?

No. Do NOT mount the iso. I assume you have the iso as a file in your Download directory. You cp the file, or dd it to the USB.

You do:

# cd /home/$USER/Download
# cp iso.file.spec /dev/sdx

BTW: you could also use the netinstall. The installers on the netinstall the CD and the DVD are exactly the same. The amount of SW coming with the media are different.

So I mount ISO and then use general path instead of pointing on every directory of it?

cp /mnt/iso /dev/sdc

right?

I think the easiest way for you would be that you go back and simply use 'cp' to copy the ISO onto the stick device, like so

cp iso /dev/sdc

if /dev/sdc is the stick device.
Then try with that.

The point is that your method will lead to failure later on anyhow, even if the bootloader gets started.

I have legacy BIOS possibility with my MB firmware, so both options together with UEFI.

With F12 the result will be same.

It is AMD.

Via 'parted' I create table and partition, set it as bootable; formating it after with mkfs.fat; mount both USB and ISO and just copy folders and files from ISO with 'cp'.

@r2, I had issues with Devuan 5.0.1 USB not booting on a Dell Laptop (it should have at least booted to the installer, 5.0.0 did).
I discovered that on booting USB the internal storage would be disabled. This it turns out is a Dell 'Security Feature' in my particular BIOS and the only way around it (untested) is to pre-load the USB's UEFI keys and enable 'Secure Boot'. So at that point I gave up jumping through Dell hoops, removed the NVMe and installed Devuan via a VM, booted fine when reinstalled in the laptop.

-- Enter UEFI -- Configure for USB partition as boot priority --

This is a residue from the old legacy bioses. The procedure to place the USB stick as first boot option is no more required on UEFI bioses. There you go and use the boot override. You PC should have a key to call up the boot menu (on my ASUS MBs its F8, on many others its F12 ... read the manual), and there you select the stick with the uefi prefix.

Give it a try, maybe this is the culprit.