I really wanna take part but I'm kinda scared because I know absolutely nothing about any kind of Assembly language. I only know C++ and I don't know if it will be good enough for this. Should I still try my chance?

I say that you should give a try. If you have some C knowledge there are some C-based development kits, like SGDK (Sega Genesis/Mega Drive) and GBDK 2020 (Game Boy).  If you only know C++ there is a C++ engine for the GBA https://github.com/GValiente/butano

PC games also count, if they're for DOS or Windows 95. Open Watcom is a little archaic - but it runs on any modern platform, and will cross-compile to everything from bare 8088 COM files to OS/2 executables. It supports C and C++.