Dear Salwa,
I am a native American, but I have traveled, lived, and worked in about 30 other countries, so I have some basis for comparison. In addition, I have worked professionally with immigrants, so I have some understanding of the challenges and pleasures that they face.
The USA does offer an enormous amount of freedom and opportunity to its citizens and immigrant residents. We are a country of immigrants, although there is some political backlash against immigrants now, as there is in other countries.
The American economy has suffered along with the worldwide economy, but it is a diverse enough economy that it still allows many people to thrive. In addition, we have every kind of climate, from tropical to arctic, and communities that vary from tiny rural villages to very sophisticated cities. There is somewhere in the USA that will feel like home to you.
Should you immigrate here? That depends on the kind of person that you are and what you are seeking. Unlike some countries, the USA does not have a very strong social "safety net". We still don't really have universal health care so that seeing a doctor or a dentist, or going to a hospital can be ruinously expensive. In many places, there is very little public transportation, so you must own a car and be able to drive. Emloyment conditions are not usually cruel or dangerous, but salaries and benefits can be poor. In many cases, the employer has the right to fire you without cause. (Unless you are lucky enough to join a union).
Americans work very hard and very long hours and vacation benefits are not as generous as in the European countries. Because of this, Americans often put work responsibilities ahead of their family time, their social life, and even their own health.
You should be prepared to look for a job and to take even a very low-paying or difficult job at first. Americans admire self-reliance above all and they will support and encourage anyone who is trying to get a better life. The people who work and try hard are usually promoted and get better positions.
If you want to succeed in the USA, you need to be prepared to learn to speak, read, and write English. Americans are notoriously non-bilingual and they expect immigrants to learn functional English very quickly. (Hospitals and schools try to provide the necessary interpretation services, but not always very successfully). There are many schools and programs to help immigrants learn English.
You need to be prepared to be tolerant. We are a multicultural, diverse society with freedom of religion and speech. It is illegal and punishable by law to discriminate against anyone for racial, gender, health, or religious issues in employment, health care, or education.
Even if you really disagree with other people's choices, their lifestyle, or their sexual behavior, you are expected to be courteous and tolerant towards them. (Unless they are affecting you directly, of course). If you really dislike gay people, or very religious people, or people who are not very religious, or people who are very different from you...you won't be happy in the United States. "Live and let live" is our motto here.
Some people think that the USA is a very dangerous place to live. We do have more guns, more murders, and more people in prison than in most parts of the world. However, actual violence is largely confined to certain social classes and areas and does not affect most people in the population. Much of the violence is related to drugs, severe social pathology, or poverty.
Canada is very similar to the United States, if you prefer a quieter, perhaps safer, country. However, it has only about 1/10th as many people as the USA, so the economic opportunities are somewhat more limited. It is also bitterly cold in much of the country and there are fewer large cities. (Brrrr. We love our Canadian cousins, but we don't necessarily want to visit them in January).
The USA offers a vivid, exciting, open, tolerant way of life and enormous opportunities for education, careers, and creative work. Immigrants from everywhere have suceeded here. Our president's father was a Kenyan economist who had studied here! If you are willing to take on the challenges of adapting to the language and the lifestyle, working hard, and adopting the American attitude of eternal optimism, you can be very happy here. Welcome.
Whatever the choice, I wish you the best,
OneSojourner