how do i get rid of history pages along bottom of opening page

Thanks for the screenshot. This provides useful clarification of your issue.

You have encountered the iPadOS “Shelf” - this being a feature of the revised iPadOS multitasking environment. 

iPadOS permits you to have multiple App windows (or “instances”) of the same App - each window being self contained. The shelf, when triggered, shows a thumbnail of each window an App.  In this instance, what you are seeing is not a previous search history, but is an entirely independent Chrome browser window.

For example, if you have three running instances of Chrome, each with its own open tabs, you will see three thumbnails corresponding to each running instance of Chrome - plus a button to open a new Chrome window. Simply tapping a thumbnail will switch directly to that running instance of Chrome. Each App - such as Mail, Safari, Notes, Calendar, Chrome etc. - has its own corresponding shelf.

Individual App windows can be closed directly from the Shelf; just swipe the unwanted thumbnail off the top of the screen. Note however, that Multitasking and associated Shelf functions cannot be disabled.

This article from Appleinsider has a useful explanation of this feature along with many of the updates to multitasking:

https://appleinsider.com/articles/21/08/12/how-to-master-multitasking-on-ipad-and-ipad-pro-in-ipados-15

The iPad User Guide is also a rich source of frequently overlooked information. The Guide is available both online using a web browser (such as Safari), or as an Apple Books download:

iPad User Guide - Apple Support

https://books.apple.com/book/id1567104892

Supporting screenshots are both permitted and invited where they are both appropriate and relevant to your post.

Screenshots can be posted with the image button at the bottom of the editing window: