1st birthday party-help!

so what do people usually do for food? I feel like I lived under a rock and never went to birthdays other than my families. and for my birthday growing up we always did a full on cookout (bugers/ hot dogs the works). but I'm trying to not spend a fortune because we are probably going to have a lot of guest. and secondly we won't have a way to grill out. my mother in law keeps saying do chips and dip and a cake and let that be it. but I just don't know! it's her first birthday.