OpenArena build.sh error ndk-build not found

When I try to compile openarena using build.sh some files are processed and then I get ndk-build not found even though I have android studio installed on ubuntu and NDK package installed in android studio. And I just want to change the ioquake engine to add my changes there and replace library with engine in openarena android. If there is a way to make it easier please tell me about it.