1. At last I had no chance to join the show, for I was lacked of confidence.
2.In nowadays competitive world, it not need the always successful man, but need the man who can face.
1.lacked 改为 lacking,be lacking of...固定搭配,意为 缺少……2. 第二句的话错太多了,太过中式,根据你的意思我重组了一下: This competitive world does not always need successful men,but those who can face challenges.