I can't manage to upload my code to my Ardino Uno!

You should see something like this during uploading:

avrdude: Version 6.3-20190619
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch

     System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"

     Using Port                    : COM4

I mean the port, on Windows it's COM on linux and MacOS it's dev/...
I can see you have selected some Bluetooth device as your com:

avrdude: Version 6.3-20190619
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch

     System wide configuration file is "/Users/leoabbott/Library/Arduino15/packages/arduino/tools/avrdude/6.3.0-arduino17/etc/avrdude.conf"
     User configuration file is "/Users/leoabbott/.avrduderc"
     User configuration file does not exist or is not a regular file, skipping

     Using Port                    : /dev/cu.Bluetooth-Incoming-Port

Yes. Your errors are all in these lines:

void loop() { // You should not have a '}' here.
  int switchState = digitalRead(2);
//^ You forgot to declare switchState by specifying a type.  You tried to use an undeclared variable.

  if (switchState == LOW) { // You should not have a '}' here.

A handy tool for seeing if the problem is you code or the upload process is available in the IDE.

Next to the “upload” button at the upper left corner is a “verify” button.

If the code doesn’t verify, fix it, uploading it will fail.

Until you can read through the errors and instantly see which is your problem. That is to say, I still verify quite often as I tinker, always trying to maintain code that complies or just to catch things ahead of time like failing to declare a variable or like that, missing semicolons, unclosed quotes &c.

a7