I have seen the price of bitcoin is very high and has exceeded 15000 $ for one bitcoin, and now the price of bitcoin is under 10,000 $ and maybe this is my chance to buy bitcoin as much money as I have and hope to get enough profit for my economy in the future.
am I wrong with this step?
Yes that is possible, you can get a better life through Bitcoin. The best thing to do will be to invest now that the price is very low and have patience to cash out in a long term. I hope there will be a Bull run next year or next two years, so if you can have that kind of patience just invest and wait till then and you will how things will change for you. It worked for others and all it took them was the same patience.