on developing links is the google page rank is the same for all the web pages or onnly the home page and if only the home page how can i improve my page rank of internal pages
Not all the page will have the same page rank. Most of the time, the home page will have higher ranking (usually 1 or 2 rung above) but sometimes it is possible that your sub pages can even rank higher as well but this is rare. The reason is because it all depends on whether the individual page has more backlinks or the content is viewed as more important with high ranking keywords.
SeoBum is spot on with his answer. You could also try to increase the page rank on some of your inner pages with some deep linking.