Research on the Wiki.
But you will need some Javascript skills - or to find someone with the skills who program it for you (perhaps for a fee esp. if your site is a commercial one).
Fabrik is a technical tool - if you are prepared to keep things simple and stick within its limitations, then it is a lot less technical that programming it from scratch, but it is still technical. If your requirement is VERY straight forward, you can achieve it without any PHP / Javascript programming just by reading the Wiki and experimenting until you work out how to do it, asking for help if you have exhausted every other avenue and cannot work out how to do something. If you want to do anything other than basic Lists and Forms with basic elements, then you start to need php and / or Javascript skills, and sometimes SQL skills too.
To take this requirement for start and end dates and an elapsed period between them as an example:
Fabrik does have the ability to put in start and end dates without needing to add php or javascript. But...
If you want to constrain the date fields to e.g. not allow selection of a date before today or more than a year in advance then you will need basic Javascript (to tell the date picker what dates to disable).
If you want to calculate the difference between two dates, then you will need to write some simple php code.
So you might be better off, stepping back for a bit and ask for advice on the best way to approach your overall requirement. We can probably advise you on whether Fabrik is the right tool for you given your own level of technical skills, and how easy / hard you will find it to do using Fabrik and perhaps steer you away from the harder things to do.