Could someone please help me with getting the "Week of the Year"
full code RTC to Serial Print would be fantastic 
Sorry but I am new at this and it is doing my head in.
What clock and Arduino are you using ?
Just decide which day of the week you want to start counting from and make a look up table to calculate the week number . Only 52 weeks , use a spreadsheet and copy over .
I don’t think you can get a week number direct.
There may be some clever algorithms - have a google
Get current date/time in seconds.
Get date/time in seconds for midnight on December 31st of the previous year.
Subtract to get the date/time in seconds since the start of the year.
Divide by 60 to get date/time in minutes since the start of the year.
Divide by 60 to get date/time in hours since the start of the year.
Divide by 24 to get date/time in days since the start of the year.
Divide by 7 to get date/time in weeks since the start of the year.
I guess you are aware that there are several week numbering systems in use: