Do i need many relevant backlinks? I have read in an article that even a backlinkless page could be at the first page of google. How to do that? Ranking on first page take a lot of SEO.
You need to get a lot of relevant back links from different sites(different IPs). If the keyword that your are focusing is not a competitive one(less than 100 searches/month),Then you can get to the first page of google with a little ON PAGE SEO.
Getting a top rank for every keyword is very difficult so I would suggest you target those keywords that have enough searches but less competition and offer a high-quality content to the visitors. Its also important to have a lot of quality backlinks to your website. Here is a good blog post on How to get First Place in Google