Find all your website's backlinks coming from unindexed domains, by using Monitor Backlinks filters. Click on 'Filters' and then on “Domain and Page not indexed”. When you find a backlink you want to remove, add a tag to your link by clicking on the settings icon on the right side of the backlink row
I think you meant toxic or bad backlinks pointing to your website.
The process is called link detox. First step would be to conduct a backlink audit to know from where these bad links are coming from. The best tool I would recommend you to use Google webmaster Tools but there are many to do so.
After signup, go to your Google Webmaster account.
Select your site > Traffic > Links to Your Site > More > Download latest links > Export to .CSV or Google Docs
After you have these links you can contact those website owners and can ask to remove those backlinks.
Its a process and needs commitment and expertise. If you are not sure how to do it, you can hire it from freelancer, upwork or Yooker.com.
Yooker is micro-job marketplace specially for seo and has many people you can rely to do the backlink audit. It won't cost you to join the site, and after you find a suitable freelancer, you can assign them with your requirements. I would suggest you to hire some one with good customer feedback or similar experience. You are going to need paypal to pay after your toxic backlinks are being removed.
There are many types of toxic bad links occurs in website as spam blog comments, also dead links too. Which one of them you are talking about?
If you are looking for these kinds of toxic links then you can delete bad spam comments from your website.