So, for build.gradle.kts u need to go to libs.version.toml and there on[version] okhttp = "4.12.0"

on [libraries] okhttp3 = {group = "com.squareup.okhttp3", name = "okhttp", version.ref = "okhttp"}

and on build.gradle.kts dependencies implementation(libs.okhttp3)

Have a nice day :)