-v: unexpected operator error in WSL agbcc build

[bitKoder]

I am building pokeemerald on my Windows 10 PC according to the tutorial on the github repository.
I have cloned the pokeemerald repo and then the agbcc repo, but when I cd into the agbcc folder and run the

./build.sh

command, it gives me these 2 errors:

./build.sh: 7: [: -v: unexpected operator

./build.sh: 14: make: not found

If I ignore it and go ahead to run

./install.sh ../pokeemerald

I get this error:

cp: cannot stat 'agbcc': No such file or directory

Any advice on how I can sort this out?