Keyword research is the initial step of seo.if you have better knowledge about keyword research.then you have learned everything in seo. why? you have 2 options.find low competition keyword and rank with few comments and guest post backlink and rank or work on any keyword and make strong backlink and rank your website.
if you will find fruitful keyword you don't need so many backlink you can rank with few backlink sometime just have to good social sharing.and no backlink are needed for ranking .if you have written a quality article as compared to your competitor in terms of content length and in term of define word,images,bullets,info graphics,user experience and on page and on site you have done a great job.Because low competiton keywords are those on which no or few articles are written on that, but a lot of people are searching for the keywords. You find, and then rank them by writing articles.
Just You need to find low competition long tail keywords and rank them.when your site get old and good content then your site rank short tail keyword too