Jump to search box = Alt+ F (or Alt+ Shift + F if Alt+ F is processed by your browser, e.g. File menu), Then hit "enter" for forms mode unless you have JAWS 10 or later and you have the Auto Forms Mode enabled where you can down arrow into the edit field and Forms Mode will turn on, or if you have the "Navigation Quick Key Delay" setting set to anything other than "Never" where the Forms Mode will turn on automatically after a specific time, then type your word(s) and hit "enter" on your keyboard. JAWS should start reading the main article (If you jumped to an article).
It can sometimes be helpful to know what the page looks like to sighted users. All pages on Wikipedia have the same format.
Main article space
When you open a Wikipedia page JAWS will start reading the "article". There are several tabs on the top lined up like recipe cards above the content of the article and below the static links along the top. These tabs are specific to the current article. (links to an article describing the function are followed by short cut keys)
A Search boxAlt+F, Then hit "enter" for forms mode unless (see above), then type your word(s) and hit "enter" on your keyboard. For a search box in which the cursor is already focused, use www.wikipedia.org
The Toolbox which is another Navigation box that is article specific and usually contains the following links.