I love coffee myself and always have to have a cup of coffee first thing in the morning.
If I don't drink a cup of coffee in the morning I am not fully awake or energized for the day.
I drink up to 12 cups of coffee per day which is enough for me.
The optimal safe amount of coffee to drink is between 6 to 8 cups of coffee per day but drinking 12 cups of coffee per day is not gonna harm you.
But you should stop drinking coffee at least 2 or 3 hours before bed because coffee can keep some people awake.
However my sister gets better sleep when she drinks coffee and I wish coffee would help me sleep but it keeps me awake.
Coffee can cause jitters in some people.
But coffee is also good for your heart and can help improve your heart health and may even prevent dementia and other diseases including cancer.