Guys, If a girl came up to you and said she liked you, what would your reaction be?

Okay so I have a crush on a boy and my mom told me I should just go up to him and tell him I like him. I was thinking about it, but I wanted to ask you guys. If a girl came up to you (assuming she's pretty and nice) what would your reaction be or what would you think of that girl? If you didn't like her would you be awkward around her now that she told you that or would you just keep talking to her normally and still be friends? And if you did like her what would you do? I wanna see if he just sees me as a friend/acquaintance or if he likes me back.