You have to concentrate on on page seo to get best ranking on google. Very important on page techniques are following a) use long tail keyword b) unique content c) image optimization d) meta tags as google require the limits e) use internal links
Get page one for which search term? Gambling is a very competitive niche and also difficult to rank well for due to many websites won’t link to gambling sites due to them being high risk getting involved with. Then of course you also have the fact there is a lot of well established big names with big budgets. Your question is very vague though no specific keyword, and explanation of your site simply states it's about gambling. Is it tips on how to gamble? Advise for gambling addicts? Is it an actual gambling site with games? If you are struggling to explain your site here on a question about your website I have a feeling your website won’t be doing the job very well either. The process of Search Engine Optimization (SEO) has many areas to cover, yet you focus solely on the end goal of how to get page one for "Keyword".
Yes, I totally agree with you because is not piece of cake for gambling site rank in search engine due to experts apply doorway techniques on it.
Aside from English tutor, you need to search for blog sites that are accepting your website field then propose a great content for them the build relationship to establish your business.
Gambling is a competitive niche. So competitor compare your website with the top websites which are rankings in your targeted country or area. You can use SEMrush or Moz to do this analysis and then you will know where you stand. I am sure, you will need lots of HIGH quality content, lots of backlinks form same niche and good on page optimization. Don't forget to keep your website super fast for Mobile.