How do I download and start using CiviCRM if I know no coding? Is it possible? Is there any easy step by step tutorial?
The simple answer is YES, it is possible to use CiviCRM without coding. You will need hosting and installation, and if you do not want to do that yourself either there are enough suggestions in the other answers. But I concur with William that you would best start with reading the user guide.
CiviCRM is by its nature a technical system and requires some technical understanding (or the willingness to learn) to get started with it.
I would suggest that you start by reading the user guide.
Alternatively you could work with a CiviCRM partner and get them to set CiviCRM up for you. Some partners offer hosted CiviCRM systems that you can use without worrying about the technicalities of hosting it or setting it up.