I try to buy Bitcoin now because is a period of my life that I can invest 300-400$ per month do you think that Btc is a good investment option for me and the range of the money I can invest monthly ?
If you have $300-$400 every month then I think half of that money can be used to buy bitcoin and the rest can be used for daily needs with family. Everyone has responsibilities and maybe in living life not only thinking about investment alone because on the other hand we also have to think about the needs of life as a support for our journey in this world. There is no such thing as too late in investing, in fact the problem is when you haven't started because you are worried that you will always say it's too late.
Invest the amount you can afford and do it consistently at all times based on the purchase period you apply. Bitcoin will give you financial freedom if you understand the pattern and if you don't want to look more difficult then buy and hold the bitcoin you have for the long term so you will wait for the moment of increase at the next ATH.