Help with background removal

Hey guys, im new to illustrator and don‘t know much about it yet. I want to remove the background a picture I got from google but I don‘t know how to do it. It is not a vector i want to note. Is it even possible? I watched people on youtube who got rid of the background out of any picture they got from google but I just can‘t seem to figure it out. Would be glad if someone could help me. Thanks in advance.