first time drinking

okay so im going to a party soon and ive never been to a party before lol . im a little underage and im aware that i shouldn’t be drinking too much. Its reallyyy normalised in my country to drink in your teens. However ive never done it before and i have no idea of how alc works. I don’t want to get wasted but i do want to feel it a little. I have emetophobia which means i am really scares of throwing up. I don’t want to have to throw up. Im about 5,7 and weight about 62 kg ( girl) how much should i drink?