how do I find line: 459 of https://xxxx.com/.

How do I find the area to correct: I am checking sites with Why no Padlock? and on several of them there are problems and it says find line 123: of https://xxxx.com. I used to go to appearance/editor, find the line and make the correction. Where do I go now? Where is the html on a wordpress site?

Thank you for any help. I have to chase this down on several sites.