Update to ios 26.3 or not?

Guys I have a iPhone 17 256 gb version I got it around one month ago it’s working smoothly,now I have received ios 26.3 update so should I do it or not because I have heard ios updates drain battery and take a lot of storage I don’t want to lose 15 to 20 gb storage plz help regarding this and explain me the battery drain issue what does it mean.

Ps:New apple user(it’s my first iPhone)