hope I got right what you need with this quick solution. There might be others as well.
Make a table with your two columns Code & Sections. This is your template database and you can fill it with all the code & sections you want to use as buidling blocks. Make sure “Sections” is your primary key (the one with the flag icon).
Screenshot (click to expand)
Now make a new table, again with two columns, one two pick the section, the other one to automatically load the code.
Make “Choose section” a ‘Table Lookup’ column from the template database (without multiple select).
In the second column, I named it “result”, enter this formula:
Now you can patch together your code. Just choose one section per row and the code will appear. You can than copy the whole column and paste it into mailchimp.
Notice: it will also copy the column title (“Result”), so you have to remove it after pasting it in. Haven’t found a solution without that