For me i casually without noticing it experienced telepathy troughout my life and I mistook it for empathy. I thought I felt sad for someone for example, turns out I feel their emotions. I discovered it when I began feeling certain ways that made no sense to what I was doing or watching when in a really special long distance relationship. I texted her if she was thinking about certain things, at first she thought I had hacked her webcam. But when I got details of her thoughts correct it sparked experimentation. The tricky part is that the line between this and imagination is very thin, so for the sake of not going insane I only take something as telepathy when confirmed by a physical human. But we have been able to do it many many times and she hasn't been the only one, although by far the most vivid.

If you want a fun podcast on this sort of stuff look up The Telepathy Tapes.