go mod tidy is used to remove unused dependencies from the go.mod file
so, apparently Go doesn't have access modifiers because it isn't an object oriented programming language
what is used to denote an access modifier is: the method usually begins with a capital letter (see packages/helper/helper.go) when the function is public, and with a lower case letter when the method can be accessed only at package level
i found that interesting that's why i'm writing this down
you can use the short := to declare a variable, making use of the type inference provided by go on the other hand, you cannot do this when declaring a constant when doing so, you must declare it explicitly, eg.:
const Constant string = "i'm a constant"
using string interpolation in go is pretty straight forward
just write it like this fmt.Printf("%s", string) (take a closer look at the docs here.)