Hi Anjanesh, welcome to the forum!
I remember listening to Yanni's "Keys to Imagination" album waaaaaaay back when I was in graduate school in the mid 1980s. He was one of the first new age composers I had heard, and his music helped spark a love for new age music in general. (Although now there are other artists I like better.

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Yanni's music is very synthesizer-heavy, so if you want to play his stuff then, yes, a digital piano or keyboard would be the best way to go. A digital would make sense for other reasons, too; they're cheaper than most acoustic pianos, so they're often a good choice for beginners who aren't sure whether they're going to stick with lessons or not. They're also much more portable, and you can play them at night with headphones without disturbing others.
As to where you start, your first big decision is whether to self-teach vs. take lessons. Self-teaching is certainly possible (many of us on the AB forum are doing so, myself included), but personally I think you will make quicker progress if you took lessons. If you do decide to get a teacher, make sure you have a conversation with the teacher about the kind of music you want to play, and make sure the teacher is comfortable teaching that genre.
If you don't want to take lessons, one approach would be to work with some of the methods book series out there, like Alfred's or Bastien. Those will teach you basic techniques, but they won't include new age music or Yanni in particular, so you would need to supplement that on your own.