I Need Your Help Guys

Hello all, I inherited a large stamp coleccion (3 or 4 thousands) from diferents countries arround the world but mostly from my country. I try to figure it out what to do with them so I decided to sell some of them and with the money start by organizing (the way it should be preserved any coleccion) the one that are from my country, expanding them and trying finishing it. Im now asking for your help in trying to identify the stamps, their value and if its posible a place where I can sell them (online). Also if you guys can tell me a manual of some sort or videos to lear the basis of philately cause am allmost cluless about it.
This will be my first photo and im going to start with United State of America.
Ps. Sorry for my english its not my first language.

Welcome, and I hope that you enjoy your new collection. You'll find that most stamps are worth very little in terms of money - good because you don't need to spend a lot of money to get them, bad in that things like the US stamps you've shown would be very hard to sell at all as a group.

Fun hobby. No $$ here. Keep on learning and collecting.