Hello...Is Guest Commenting is helpful for making good back-link?

Guest commenting to the blog will helpful..it will create additional links to the site and boost the website to get good rank.

Yes guest commenting or posting is very helpful as it provide more quality backlinks and also improves ranking.

Guest commenting provides nofollow backlinks which are helpful to redirect traffic from various external webpages to your website.

Yes, Guest Posting is certainly one of the best ways of getting a backlink. you just need to make sure that you approach high-quality guest posting sites like Buzzfeed, Huffington post etc which have a higher domain authority.