dynamic 365 online customization

Hello everyone,
I am a new user of dynamic crm 2016 (Dynamics 365 online). Please help me to understand its functionality...

how can i know the setup of particular form, entity etc , as we knew in ax by right clicking and selecting "go to setup"  . i have an issue in search function and its result... but i cant able to add another column in this search result... because i don't know what is the setup of this search result.. and how we can code for form and other things... is visual studio require or not?