Building backlinks only doesn’t guarantee to be successful with blogging.
You must have ability to find low competition keywords. It depends on niche too.
If you have chosen a highly competitive niche, it will be harder to rank first, you need more budget in that case.
If you have chosen too specific niche, you will run out of keywords to write about.
If you are a newbie, give some time to read stuff about keyword research and competition analysis too.
If you have learned these things, you can start building links.
And yes! Backlink works!