I've never known or heard of any free blogger blogs earning any decent amount of money in anytime let alone in just 12 months.
I've also never really seen blogger blogs show up in any Google search I did unless the blog was indexed and was ranking on like page 15 or something.
If you want to make money with a blog you should not go for free services such as blogger or free wordpress hosting.
You should signup for a web hosting company for around $4.00 per month and purchase a domain for around $10.00 per year and install wordpress on the web hosting account which will make the blog more professional and help it rank better in Google search.
But even then unless you're really lucky or have money to spend on advertising then it will take some time to get the search traffic to your blog which will be needed to earn money blogging.
Search engine optimization and ranking is a long term process and can take 90 to 180 days to rank content in Google search.
So be prepared to wait awhile to see search traffic to your new blog posts.