I would expect this to have been mentioned already but I have not seen where. This question seems to be in many parts and, though there is a theme to these for the OP, the topics seem reasonably distinct:
How to e-mail Google?
How much advertising on GMail?
How to export contacts from Yahoo! Mail?
Will exporting contacts from Yahoo! Mail remove the data from Yahoo! Mail?
How to import contacts to GMail?
Does GMail allow subfolders?
Individually they seem mostly on-topic and not subjective while even collectively not requiring an entire book to answer, yet together they do not seem to me well-suited to a Q&A site. On-topic has "If your question ..." but no specific mention of something like "one question at a time".
"Questions with too many possible answers or that would require an extremely long answer" from here might be intended to cover this but there the context is that the plural is used for different posts rather than questions within a single post and I understood "too many possible answers" to be intended to apply to an imprecise question rather than to a suite of questions (for each of which there may be few possible answers).
Should the question in question be left as is (I am misinterpreting the scope of Web Applications) and if not should Help be amended?