I would like to know which font license I should buy for use in a company logo? I am going to use the logo in my web application, in advertisements and everywhere the company logo appears.
You'd typically buy the standard license. With a few exceptions, most commercial fonts allow you to use it as you see fit. If there is an exception, you'll see it in the license.
Do note, however, that the font you decide to use for your logo is not typically also used for everything else. That's not a hard and fast rule, but typical.