How to handle repairs?

I got the day off school today; because since my mom has gone away for work purposes for 3 weeks. Its up to me to handle the business with the cooker repair man... I was hoping to get a bit of advice because tbh I seriously don't know how to handle this.

I know not to let strangers explore the house other than the room in question and the bathroom which is right next to the kitchen but that's all I know really. :'( xxxxx