Can't upload any program onto Arduino Uno

HELP!

I am trying to upload a program onto my Arduino Uno (even happens when I upload a blank program). And I am getting this error:

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 "/private/var/folders/5c/brbfv9rd6yq4x6bmv9g4vyph0000gn/T/AppTranslocation/F9828822-D6DD-486D-803C-C99CB312C966/d/Arduino.app/Contents/Java/hardware/tools/avr/etc/avrdude.conf"
User configuration file is "/Users/forestedwards/.avrduderc"
User configuration file does not exist or is not a regular file, skipping

Using Port : /dev/cu.usbmodem14111
Using Programmer : arduino
Overriding Baud Rate : 115200
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x00

avrdude done. Thank you.

An error occurred while uploading the sketch

I have my board set to Arduino/Genuino Uno, and my serial port set to dev/cu.usbmodem14111 (Arduino/Genuino Uno)

I have uninstalled and reinstalled the Arduino IDE to multiple versions and still get the same error

I was able to upload programs perfectly fine the other day, and I have no idea why it isn't working now.

Help is very much appreciated, thanks!

Do you have anything connected to it?

It might be possible that you have something connected to the rx and/or tx pins of the uno. If this is not the case then there's probably some problem with the board itself.

I saw an error like this when using a Redboard and, in that case, I had to quickly double-click the reset button on the board to get it into bootloader mode. You said Arduino Uno, but it's maybe something to consider.