is wordpress better than bootstrap?

Answer 1

You're comparing apples to oranges. Read about what each of those are on their respective sites.

Answer 2

to learn WordPress you need to have a good grasp on PHP as well

Answer 3

WordPress is a Content Management System (CMS). It allows you to create new pages, upload images, adjust which items appear in your menu, and do a host of other tasks related to the content of your website.

Bootstrap is a front-end framework, which is a collection of CSS and JavaScript that works together to control the presentation of your webpage. This presentation includes the colors of your text, what buttons look like, and how your site changes when viewed on a mobile device (eg: three columns collapse to one column, your big menu changes to a little icon, etc).