Why is my iPhone 12's battery draining soo fast!??!?!?!!? PLS HELP!

For christmas i got an iphone 12, Almost right away after doing the initial setup i noticed that the battery was draining abnormaly fast, like for instance i would play a game for 5 mins (Wich is not demanding at all eg. Tank stars ), then my battery would have gone down 5 percent or even more in other cases! I have done research on the problem but most of all the posts are complaining that the iphone 12's batteries drain up to 30% over night wich is not the problem for me. I even compared to my previouse phone wich was an ipone se (2016) and it would BEAT the Brand new Iphone 12 in battery consumption (and also the se was at 88% battery health). PLEASE help!

Have a great day.