Hi, I'm a beginner. This is my third day learning bitcoin. So far this is my understanding on how to earn money from it, pls pls correct me if I'm wrong so i can get better understanding.
1. Mining
2. buy low sell high (this is what I'm interested in  ).Questions:
a. Why some people use localbitcoins to trade? Why not using the official www.bitcoins.com? WHat's the difference?
b. and the money you received will be using paypal. I don't like paypal. Is there any other method beside paypal where i can receive my money safely?
c. Wallet is where you keep your bitcoin, wallet ex is coinbase, coinjar, etc. What is the difference between blockchain.info and your wallet?
d. i've got an offer to buy bitcoin from $55, while current bitcoin price is $2500. They said they're using platform. How do they earn their money from bitcoin? are this trading company joining people's $55 and buy 1 bitcoin in a group or what?
e. what's the difference benefit between EFT Bitcoin and buy low sell high bitcoin?

Fingers crossed someone will clear my mind by answering this. Thank you all.