I am a beginner of coding what language I should prefer first?
I think that you should start by learning "algorithm" in order to get the way of thinking logic so that you can translate any idea to a psedu code. after that I advice you to start by python in parallel you can learn html and css which are so simple.
html -> css
I'm a fresh beganer so to decide is not easy ,but this system of yours waisting time & energy.