Gspr

Hello there, I have been trying to install forge 1.12.2 to get pixelmon, but when i double click or try the cmd command to open the installer, i get nothing but a black screen for the former, and an error (Error: Unable to access jarfile forge1.12.2installer.jar) for the latter. I have checked some other posts to see if something could fix my issue but nothing has worked so far. I have downloaded Java Version 8 Update 251 as recommened by the website. Could anyone please help me out with this? Thanks for your time :)