I Was Selected by the System at the Beginning, I Want to Become the Sixth Permanent Member

When the war comes, the people at the bottom are like lambs waiting to be slaughtered. The protagonist, Mo Yu, obtained the arms system by chance. As long as he continues to complete the mission, he can obtain various weapons and equipment. From then on, the protagonist develops like a cheat. Steel suit? Controlled nuclear fusion? Flying fighter? I want them all!