Demo account :
If you are new, you must try the demo account before starting Trading to build the skills and for a better experience. many trading apps provide demo accounts where you can learn about the behavior of the market in different situations.
It is not a must that every trader must practice trading with demo accounts. It is just advised that you start with demo trading because of the lessons that can be learnt from it before trading really and to avoid financial lose. If a trader who is new can handle the losses financially from not trading on a demo account or not having enough patience to demo trade, then they can start trading normally and then handle the losses and struggle to beat the disappointment that comes with the failure of not having the patience to learn. It is still possible to learn through it, but it will only be if you are strong willed and financially capable.