I don’t have updates iOS 13 plz give me update iOS 13

Your old iPhone "6 Plus" is at the End of upgrade path.

No newer versions of iOS exist; due to hardware age.

Answering your own question, only makes it harder

for accurate replies to be seen.. Because your error

repeats itself to be at Top of the list of answers!!

iOS 15.6 presently is current update/upgrade for iPhone..

"Supported" models are listed in database, to reflect this.

Supported are "6s, 6sPlus, SE (1st, 2nd, 3rd gen), 7, 7Plus, 8, 8Plus,

X, XS Max; & all models of iPhone 11, 12, and 13 series" are listed

& supported iPhone models; and can further run newer iOS.