Thinking of legally changing my name to have two middle name but I don't know?

Hello, I am a transgender individual and I managed to come up with a first name for myself then it hit me if I wanted a middle name. I wasn't born with a middle name, so when I legally change my name, I might add one right? I found a middle name I want now then it hit me can you have more than one? I heard some people even have 3. Although I hardly see the point of a middle name let alone 2. After all, your middle name will hardly be used unless it is for a government that requires your full name. most banks don't even read your middle name also. Plus I could see where this becomes an issue such as being character limited. I mean is it done for more fun rather than function? After all, I heard some people just write in only one middle name if they have more then one or just abbreviate their middle names.