1. I don’t know how to accomplish what you want here. Those inputs should be empty to begin with for every new visitor that hasn’t commented yet. If those values are showing even for new visitors then it’s probably a caching issue. There’s also a small chance that this is due to your site being hacked.
2. The previous topic poster before you just asked this very same question.
https://ronangelo.com/topic/frontier-theme-comments-form-un-needed-text/