To finding and removing low quality link. You have to work on seo tools like seo profiler , sem rush , moz etc.
1 - Firstly you have to analyse your site baclinking in any of seo tools.
2 - Make a list of all low quality bad link.
3 - After that use webmaster and any other webmaster alternative...
For finding low quality backlinks. You simply have to use seo tools like seo profiler , moz , semrush.
Analyse your website link on that tools and remove all links whose pa/da is below 25. You remove these link either from google webmaster or use other google webmaster alternative tools.
thank you.