search engine algorythm

I have a website for a window cleaning business which I need help marketing and possibly edited with a fresher look as some of the links don’t work. I target a few towns in close radius. Anyone specialising in the SEO field or could point me in the right direction, please reply to aid me in...

so if I have already published an article but I want to add some keywords or want to change some phrases is this ok to do so? if I have a crappy article ranking on position 90 and I rewrite the article could I improve the ranking even to the first position?