這樣寫文法有錯嗎？

文法和組句的方式都好多不對，而且一句包含這麼多資料要讀者不透氣地看亦不是上策。另外schedule作為動詞一般用於未發生之前，但句子卻用past tense (was)，看來是報告已生發生的事，但內容卻用present tense，這些混亂的含意難以明白和改正。我按你日期估計是已過之事重寫。

The Orientation Program for internal staff was held on 15 July. It provided staff with information on the latest coprorate direction and general regulations and proceudres. It also highlighted some issues on compensation & benefits, training and employee relations.

希望有層次地表達你想講的東西。

The Orientation program for internal staff that was scheduled on 15th July, gave staff the latest corporate information and refreshed the following issues on
compensation and benefits, staff training, employee relationships as well as
general regulations and procedures.