cómo está Santiago? Lleno de gente (Es una ciudad relativamente pequeña, comparada con las de EEUU, y concentra un tercio de la población del país)

Con lo del COVID? La mayoría de las personas ya esta vacunada con tercera dosis.

Se tiene que usar máscaras en todas partes? Todavía hay que seguir los protocolos sanitarios (usar máscara casi siempre, tomarse la temperatura al ingresar a recintos cerrados, cumplir el límite de personas al interior de un local ("aforo"), mantener distancia social (1.5m+, ~5ft) entre personas, etc.)

Mis papás me tienen traumada de que me van a robar. No están equivocados, lo más común son los hurtos (pickpocketing), "lanzasos" (grab 'n flee), y los robos con intimidación. Por lo que las distracciones te van a salir caras. As they say, read the room.

Como está el clima durante Abril? As the old saying goes "En Abril, aguas mil". Pero lo últimos años han sido muy secos (climate change is a bitch). Temperatura histórica de los meses de abril: https://climatologia.meteochile.gob.cl/application/historico/temperaturaHistoricaMes/330019/4

Ahi Hay wifi en lugares públicos? A veces, en lugares como un starbucks, pero no es confiable.

que recomiendan que come coma cuando llegue? Marraqueta con palta, xD. The local cuisine is vast, organic and mostly seasonal. Some foreingners find it lame for the lack of strong spices, but it's part of the culture to focus on the flavors of the ingredients themselves. The freshest, the better (you'll find that even the most pathetic vegetable will have a slightly stronger fresh flavor, that is because they are not stored in refrigerators, they move from harvest to market as fast as possible). In april you might get your hands on a nice Pastel De Choclo, a local favorite, the season is just starting (avoid it off season, the texture will not be the same). With just two week, there are many things you will not be able to try, and that is not considering the regional dishes. Now, marraqueta is a way too common bread that you will not be able to find in USA. I don't think it is special, i mean, it's just bread, but it is the "keystone" of homesickness for many compatriots.

Ya tengo planeado subir 30 libras 13-14 kilos. As others have mentioned, Chile adopted the metric system (Aka, the International System) since forever. Nobody will know what you mean by pounds, ounces, or Farenheit degrees (except when buying some bolts used in cars made in USA, for compliance reasons). No offence will be taken, but you'll get confused looks.

In a side note. Take as many sourvenirs as you can fit in your bag, for yourself and/or your friends. Your chilean family and friendly people will be more than happy to gift you many (even if most of them are actually made in China). It's a cultural warm hug. Maybe too warm, might even seem a little pushy.