Write down your model number before searching for firmware. Searching for "Nokia G50 5G" alone is too vague.
If you need to manually flash your device to unbrick it or downgrade, you must download the specific stock firmware files (often referred to as "Flash" files). Nokia G50 - Software update - Gomibo.es How to Download Firmware for NOKIA G50 5G-- How To
Using the repositories mentioned above, find a file that matches ALL three criteria: Write down your model number before searching for firmware