Having Jewish friends stay with me and need some help

Hi there! I’m not Jewish but I have a friend coming to stay with me soon and would appreciate some help in preparing. How do I find out if restaurants/food is kosher? What should I have grocery wise in my house for Shabbat? My cat has an electric water fountain, can I keep that on? What should I have turned off at my place for Shabbat? Can I have an alarm clock on? If we walk to a restaurant/ bar can we use a debit card? I have a gas stove is that okay? Ah I havé so many questions and don’t want to make this trip too stressful for them! Any tips would be appreciated thank youuuuu