SharePoint Application suggestion

Question

Hi Team,

 

 

Using SP 2013 online and trying to implement a SP Application, i have many Application changes came from Client and trying to maintain this changes implementation date in calendar. once it is recorded in calendat one mail will need to trigger and Application team get alert changes came n all. after that Application Team will assign that work to any team member.

 

Any suggestion how i achieve this?

 

Many Thanks