Spanish- difference between gente and personas?

i'm not the best at technicalities but for your sentence it's muchas personas as it addresses the amount of persons or individuals which in this case is a lot. Gente is usually used to address a people, like "las gente de andalucia", or "las gente de catalunia" = "the people of andalucia" or "the people of catalonia". However, it's not uncommon to say something like "hola gente!" when meeting a bunch of persons. Americans would say in the same sence "hello folks!"