Hi Kiara,
Thank you for you lovely note and for the purchase of my books!

Yes such things are possible, the ability to exist in other realities, for those that have acquired the energy and discipline to do so. And there are many complex nuances to this that one must consider, but that are endlessly fascinating as well. For example, it is possible to exist in other realities where time moves at a different rate. One could for example inhabit a world where weeks in that world are only hours in this one. Being able exist, even for a small time, in this world can allow a person to live and develop a great deal of experience in what would seem to be a very short period of physical time. One could travel to this place for an hour of physical time and yet spend many days doing something in that other world that they may like.
There are worlds that are completely unlike ours where we can only exist as a sentient consciousness there by becoming something else yourself. There is a place for example where you can only be what, in this physical world, would be called a kind of cloud. As such your consciousness there defies description here. In that place you are one but can be many, you are you but you are them and part of all and everything as well in a way. What could be termed winds and movement of any kind are the most important thing in that world, and entire compositions are shared and written (in a way) by one to another, in relation to what kind of wind, at what time, and during what particular subjective state the composer is in.
There are also some considerations having to do with a person’s need to come back to this physical existence at the end of their Out of Body journey, and the choices available now and after physical death.
This is just the tip of the proverbial iceberg as they say. Ultimately, most that pursue these practices with any great vigor, are those that want to extend their individual consciousness after physical death, and to break free from the limited three dimensional binding force forever. That I would say is the ultimate achievement through these practices.

I am very happy to know that you are working so hard on your techniques Vignesh.
Being able to feel anything during the out of body condition can be quite difficult situation to deal with that first, and in the end it is something that requires more time and practice. As I like to ask on occasion, what is that you are feeling with in the first place? The double body is a construct after all, there is nothing physical about it and therefore nothing to feel with? This odd question might help you to understand the nature of your double body better.
But getting back too it; what you have to understand, is that depending on which dimensional plane you happen to be in, there is a direct correlation between what you can and cannot feel, that is what you can and cannot touch.
If you are in the out of body condition and you explore the physical realm, then your vibrational density as an out of body traveler, will make it very hard for you to touch anything in this dimension, because one dimensional frequency is essentially trying to interact with another.
But if you explore other dimensions, dimensions that are less dense from our perspective as physical beings for example, then you will be able to feel much more in those other dimensions because your travelling essence, your double body, will be closer in denseness to that other dimension.
‘The only way’ for you to be able to feel something directly in this dimension, that is the dimension that we called the physical world, is to turn your traveling body, you double, into something more dense, harder. At which time, this traveling double body would then be able to interact with the physical world to a greater or lesser extent depending on its growing density, it growing power. But this is a very difficult thing to do and it is usually only accomplished by very powerful practitioners. To do this you need to work very hard on the double body creation exercises that I describe in the Out of Body book.
My suggestion to you, is that if you wish to feel using your double body, is that you travel to a dimensions that is, from the point of view of the physical realm, less dense. Such places are to be found in areas that are more related to what we usually refer to as dream locations, the dream world, and can be accessed if you use the techniques that I mention in the book, the way of the projectionist: using the second room of the projectionist and then using different portals as I described in the book. With this method it is possible to access both lesser density and higher density worlds. And might I add, less dense does not mean less real, often times these supposed ‘dream’ dimensions are far more real, vivid, and powerful.