Writing a script on Google spreadsheet

Hello there! I was wondering if you are able to do a simple scripting on google spreadsheet for the below? 1. An approval form which will submit the data to google spreadsheet and email me of the pending approval. I will then review the data on the spreadsheet and make changes(if required) and click an 'Approved' button which will send an email to the sender that it has been approved. I shall also require a notification script which will send an email reminder to names mentioned in the approval form of their pending task. I must be able to choose the frequency of the reminders, e.g. 2 & 3 weeks before the due date and subsequently daily reminders. The notification stops when I click a 'Completed' button on the spreadsheet.