I am a US citizen and wanting to adopt my 12 year old brother from the Philippines.
Can you help me know how this will be done, how long the process will take and if
Possible how much money I will pay to process his papers?

It's not going to work that way. Green card through adoption takes forever especially in the Philippines, except in case the child is an orphan. Since you are USC, simply file I-130 for your brother, it will take approx 12 years.