window security warning HTTPS on rohan online ??

Hi I'm new to the game and when I click on my character and get to the load screen of the game the window security warning HTTPS show up.please explain it to me like 12 year old what does it mean? do Hit yes or no. its this safe or unsafe. I want play the game with no problem but its seem that this window security warning HTTP show up when I chick on my character and the loading screen show up. :( I'm bit confuse by this and very scared. I don't want play this game if not safe. I just want to play a game without no harm come to my computer. I am just old man who want to have fun and play game without the confusion so please if there any expert in this forum that can take the time to help me understand this problem and what all this mean.