I Find It Difficult To Keep These Birds As Pet, Help

I have this long interest and passion to keep birds as pet. I have severally caught some few birds which I intended keeping as pet. The shocking news is that I usually wake up the following day to meet them dead, even before I could get a bird cage. I do have this bad feelings been somehow responsible for the deaths, and I am equally not pleased not to have my long desires of keeping a bird as pet come through.
Please, I need advise on the following:
1. What could be exactly responsible for the deaths?
2. What is the name of this particular breeds?
3. Can they be kept as pet. If no, which do you recommend? And if Yes, how?

Thanks for your response