He feels his life is more structured since he started attending church regularly.

attending 是动词 attend 的现在分词形式，attend 的意思是"参加、出席"。 church 的意思是"教堂"，指基督教徒进行宗教活动的场所。 attending church 是一个固定搭配，指"去教堂做礼拜"，表示定期参加教堂的宗教仪式活动。