Data Challenge: turning massive amounts of sales order data into summarized customer data

I have a lot of data (over 674,000 rows) by 8 columns but am struggling to figure out how to work it into the data I need. There are very simple formulas for what I need (counts, if statements, averages, etc) but I can't figure out how to execute them without a ton of manual work. Further complicating matters is that each customer has a variety of orders (some have 1 others have thousands).

Attached you will find a subset of the data on Tab 1 "Data" (4 customers, 188 rows) as well as what I would like the output to be on Tab 2 "Desired" (empty rows separating customers are not necessary as I will be using vlookups to arrange the data further). If you have any idea how to do this I would greatly appreciate your feedback.

Thank you!
Andy