how do they tell different between real transgendered from fake
SSry bad english

Hi honey,

I'm not sure what you mean. Maybe tell us more, it doesn't matter if the English is bad, more you say more we can read and understand.
Hugs

Do you perhaps mean, how does a doctor or therapist diagnose someone with transsexualism, vs. something else?
If that's what you mean, transsexualism has "symptoms" like any other condition. But ultimately nobody can (or rather, nobody should) tell someone they are trans. That's for the person to figure out. It is a doctor or therapist's job to help figure it out. It is also only for the person to decide, if medical and/or social transition is right for them. It is the doctor or therapist's job to help with that too.

Does that make sense? Or was your question about something else?

If you are trying to figure out yourself, it is based on how you feel.

If you just like to dress up as a different gender expression, then maybe you would identify with the word crossdresser or ->-bleeped-<-.

But if you feel like you really are part of that gender, and want to be that gender and be known as that gender, then transgender or transsexual could be a good word for it.

If you are trying to tell whether other people are transgender or transsexual, think about this: why does it matter to you? It should not matter if someone else is transgender - they deserve equal treatment, the same respect, and same consideration as a person who is cisgender.

Nobody here is going to call you a "fake" transgender, or gossip about other people's genders (okay maybe a little bit of celebrity gossip, but not unkindness or hatefulness).