I've been working for the company that is sponsoring my green card for the past 2.5 years and some of the experiences/skills required in the Job Description were acquired working with this company. Is it valid to include those skills on the Job Description? Should I have acquired those skills before?

I completed my master’s degree last summer and started working with a company from 2 months.
I am in OPT status right now and I wanted to know, if I am eligible to file for Green Card process with my current employer. If yes can I file in EB2? I have 2 years IT experience in India If no, do I have to wait until I get H1b. Is the Green card process dependent on H1B?

My dad has a green card and went back home over 2 years ago. He is now trying to come back after being away from the US for 2 years. I was told by some people that if he stayed over a year outside the US they will not let him back in to the US even though he has a Green Card. Can you please tell me if this is true, or can I just get him a ticket and fly him back to the US?

Is it possible for me to work outside the US (for the same company that I work for now) while on green card? My company has an office in India, and I have to travel to India for family reasons. I was planning to work in India for some time, and then come back in about a year and half and apply for citizenship. I have lived in the US for about 3 years on my green card now.