following the update of the system of my MBP 16" M1 to beta 26.4 none of my external drives work anymore

Hi, firs, I see all my pages are sort in the wrong way, tjr fist is now the last one. when want to change the place, new window open and don’t know how I can close them when I want to send the window, no arrow in the right, have to serch in the adress to fond it, not easy. at a moment I had a welcome page, don’t know how. see 2 small window on the page I see but can’t close them. don’t test folder for the moment. need a tuto when it will be the public build to explain how it’s works, and please, feep how the pages are sort, thanks.