As far as I'm concerned, an achievement that I successfully accomplished is finishing an English camp in the states. There are two benefits for this.

Most of all, going to the English camp made it possible for me to meet different people and gain valuable experiences that I've never known before. This allowed me to expand my social network and broaden my perspective.

Moreover, it inspired me to make more effort and become responsible for what I do. Then, I'm able to concentrate better and this can bring about a better outcome at school. 聼起來自然嗎?

Most of all, going to the English camp made it possible for me to meet different people and gain valuable experiences that I've never had before. This allowed me to expand my social network and broaden my perspective.

Moreover, it inspired me to make more of an effort (or you could say 'made me want to put more effort into things') and become responsible for what I do. Then, I will be able to concentrate better and this can bring about a better outcome at school (or you could say 'this can help me to get a better outcome (or result) at school.

Your English is super good! Sounds great!