Critical issues help

Got a few wordfence critical issues, wondering if somoene can recommend a course of action. One of my customers said there was a porn pop up when they went to my site here: https://mattress-deals.com
https://snipboard.io/h8anvI.jpg
https://snipboard.io/W8BqUA.jpg
https://snipboard.io/AFZJVx.jpg
https://snipboard.io/FNRUv0.jpg

Thanks in advance!