Inside the page there is also the actual link to the disavow tool. If I remember correctly, you will need to upload a text file, containing the domains or url you want to disavow.
Disavow Tool is provided in Google Console for providing direction to the search engine not to follow its back links. The back links are not deleted by the search engine however it do not consider useless links to your website.
First, make list of link domain or links you want to disavow.
Make a .txt file of the list.
Sign-in to Google webmaster account and got to the disavow tool.
(For your reference https://www.google.com/webmasters/tools/disavow-links-main?pli=1)
Click on Disavow links button
Select the property and upload the .txt file.
You are done.