Help with vigotec vg-l3

Hi my wife bought me a vigotec vgl3 for christmas
… i know it isnt going to be the most amazing bit of kit but, how do i change softwear or run it with new soft wear, when i tell it to ingrave its missing letters or putting them in the wrong place

It looks like vigotec have multiple models. Can you post more information about this one? At least some of them can be flashed with Grbl_ESP32:

All i know is its a vigotec gv-l3
How would i go about changing softwear?