SEO is a compelte process of On-Page and Off-Page activities. On-Page is very importnat task for organic SEO. If your website is not SEO friendly, you will never get a good ranking only by Off-Page submissions.
I will suggest you what you require to do on your website for a good On-Page activity. Send me your website link, type of your business(a brief will be good) and I will send you my suggestions.
