Style some Joomla site items

I have a joomla site build on the purityIII template. A friend of my was styling it for me but has been fallen mentaly ill and he is not capable to finish it for a long time unfortunately. So the site is still not finished, but the basis is solid. I want to finish it for him so that he doesn't have to worry about it any more. It is only to style the site. I can add text, pictures and other stuff. The requierments for all changes are. - That they are easy to use and safe. - That they keep working after updating Joomla. - That they keep working after PHP change. - All changes must be open so that if necesary we can change them in the future. As far as I know there are 5 things that need to happen before the site can go live. 1. Style the page that is shown with the build in tag system. So that it looks like the picture in the attachment layout1.png. In the past we did it with a plug-in called multiple catagory's, and we want to switch to the native build in tag system witch supports multiple tags and cheaper and more stable 2. A horizontal menu bar on position 6. We must be able use the menu style on multiple pages with diffirent content. All code shoud be there but last I know that is wasn't alligned properly yet 3. Is a maybe we have a automatic translation module but it is placed onder the search bar. If you find a better location or in the main menu bar so that it is still visible on all pages. 4. Add a Cookie announcement as requiered by EU law. Ofcourse if possible in the same layout as the site. 5. A map system so that we can ad a map for a region of country with locations we want to show. For example all themeparks in the Netherlands. Can be an plugin that is already made but is possible with google maps and easy to add locations. 6. If you find any thing else that looks wrong. please tell me. Hope that someone can help me.