@reechi thanks for your question. This may help others too.
It is not a must to introduce yourself, but it is recommended, so people know your values, and what you are looking to do here on steemit. The more value you will give, the more other steemit users will be interested in following you, and/or read what you will be doing on future posts.
If you decide to do so, add the tag "introduceyourself"
Also, check @theaustrianguy and see what he is doing to help new people that make their introduction posts!
Regards, @gold84
Thanks for this info