Create a Wordpress Template

I have a wordpress theme. Would like to customize the same. 1. Need to add a search bar to the home slider/image. 2. tabbed post page. 3. in one of the tabs, need to add a drop down menu and when a item is selected, the results should be displayed according to the item selected. (eg, if City A is selected, an table should be displayed. In future I should be able to change the table regularly.