"Getting It" (or, Making It "Click")

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As others have said, it sounds like you're overthinking it. For example, here's a simple and complete Racket program that you can paste into, e.g. test.rkt and run from the command line using racket test.rkt (Note: Prior posters have been mentioning the use of (module+ main ...) but that isn't strictly necessary.)

#lang racket

(define (factorial n)
  (cond [(= n 0) 1]  ; factorial of 0 is 1 by definition
        [else (* n (factorial (- n 1)))])) ; e.g. in math, factorial(7) is (7 * factorial(6))

(displayln (factorial 5))  ; prints 120

Here's another example that does all the things you mentioned doing in Go. Again, you can copy/paste this into a .rkt file and run it from the command line:

#lang racket

; Example code responding to bsilver from the Racket Discourse,
; showing how Racket would do each of the things he mentioned doing in
; Go.  His requests are preceded with '...', mine are in {}


(require racket/async-channel) ; ...you start with some imports...

; ...a package name
; {You don't need that in Racket}

(define (main) ; ...a main()
  (define x (add1 7)) ; ...I can call another function that passes back the result
  (displayln x) ; ...then call another function
  (define y (* x 7)) ; ...just keep passing the data through these functions

  (define ch (make-async-channel)) ; {create a channel (well, an `async-channel`, since `channel` is synchronous)}
  (struct person (name age) #:transparent) ; {create that structure type you wanted, to be used later}


  (async-channel-put ch y) ; ...hand them off to another routine via a channel

  (thread
   (thunk
    ; {create another thread to listen on the channel (not part of
    ; what you mentioned in Go but makes a good demonstration)}

    (define age (sync ch)) ; {receive the value handed off through the channel}

    (person 'bob age) ; ...that maybe passes the result to a structure
    ; {the above line creates an instance of structure type 'person'
    ; using the passed-in value for age. Hopefully that's what you
    ; meant by 'passes the result to a structure'}

    (async-channel-put ch "Finished.") ; {tell the main thread that we're done}
    ))


  ; ...or through a network connection that was passed as an argument to it
  (define socket  (udp-open-socket))
  (define udpport (udp-bind! socket "127.0.0.1" 22871)) ; {listen to UDP port 22871 on interface 127.0.0.1}   

  (do-network-thing udpport y)

  (displayln (sync ch)) ; wait for a signal to come back on the channel, then clean up and finish
  (udp-close socket)
  )

(define (do-network-thing udpport val)
  ;...do something through a network connection that was passed as an argument to it.


  ; {I'm commenting this out because I don't want to actually deal with network code in an 
  ; example, but it would send the byte string "hello, world" to the specified host 
  ; machine/port}
  ;
  ; (udp-send-to socket target-host target-port #"hello, world")


  ; ...I need to check data at some point, I can write another function and just insert it into the flow.
  ;
  ; {Not sure what this means.  Maybe anonymous functions?  Racket's gotcha covered.
  (when (equal? 11 val) ; {check the data}
    ((lambda (v) (display "inside anonymous func, v is: ") (displayln v)) val)) ;{write another function, insert it into the flow}
  )

(main) ; {kick things off by calling main}
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