The wrong line of HTML is selected in the screen-shot. See the bottom-left of the screen-shot. This is selected (highlighted in blue):
<div class="lp-confirm-wrap">
Select this line above it instead and repost screen-shot:
<div id="lp-confirm" class="lp-confirm lp-confirm-style4 left">
These articles suggest the problem is your computer/browser(s) rather than your website:
https://solvemalwareinfections.com/2022/02/15/how-to-solve-i-datingpoint-top-pop-up/
https://malwaretips.com/blogs/remove-dating-meet-top/
If so, the good news is that only you are seeing the pop-up, not your visitors. I can’t see it. Have you seen the pop-up when viewing other websites or using others browsers to view your website? How about when viewing your website on other devices, like your smartphone?
Before following the instructions in the articles, I recommend downloading and installing Malwarebytes. The free trial will allow you to scan your computer for malware.
https://www.malwarebytes.com/for-home (Click “Free Download”)
Run a full scan. It may take some time.
Also, afterwards, run a scan with SUPERAntiSpyware, which is also free.
https://www.superantispyware.com/free-edition.html
These steps should identify and eliminate the malware. If not, we can proceed with the steps in the article, and beyond that, explore if your website is the problem as you originally suspected.