Q. Have you tried online plagiarism checker www.plagramme.com, turnitin, gammarly.com. ? Whether it is appropriate for students to use?

Plagiarism is problem for lots of college students.  Plagiarism checkers, such as the ones you listed, can be a great tool to make sure you are not committing plagiarism.  www.plagramme.com is a free option I am not particularly familiar with, but it looks like it might be a safe choice.