Hello , i really need some help from a professional. I am a newbie . Started a website and i am still trying to learn while building it.

I have seen like, follow buttons appearing on the site of the website and when you are scrolling up and down they stay on the left/right side of the screen. I hope i explained it correctly :| I really like it and want to have it on my website. I was searching for hours on google to find something but couldn't. If somebody can help , please PM or reply to this topic.
Thanks a lot in advance