Amish and first bf

Hello everyone. I am very new to all this modern stuff. I'm Amish. Or was considered. Til I got outcastes because I love the outside world more than my family traditions. To see and hear music and electronics is amazing. Back where I'm from dating is foreign. A father can arrange your marriage. I am with my mother sister and she is happy and married with 3 of my beautiful cousins. Lately this past 3 month, I've been dating a guy. We hold hands. And innocent kisses on my cheek or forehead. My aunt asked me about sex... I'm clueless. Where I'm from, it's not discuss. It's purpose is for procreating children. That's it. I am still gonna stick with waiting for marriage because I feel that the person I give my body to is whom I should be married to.  But is there anything that I need to know about this sex? How do I know if a guy is a good guy? What do I need to prepare for? How is sex like? Why do people do it for pleasure?