I have a problem with my old friend Mac air 2011
Hello everyone, i need your help. I have a problem. When i start up my mac, it freezes near the end of the start up bar, at that time, my mac's fan begins blowing heavily. Then, I have to hold shutdown button to restart. After that, I start my mac again and luckily it can open. One pop up appears. It said that "you shut down your computer because of a problem" (image below). Could anyone help me to save my mac? i really do not want to lose it. Thank you very much.
MacBook Air 11″, macOS 10.13