fopen returns non-null pointer even though file does not exist

I have a Hex file whose contents are like below:

0x14000800 0x52100000 0xD503201F 0xD503201F 0x0030A308 0x0032D138 0x00000000 0x00000000 0x00000000 0x00000000

I need to open and read this file. Below is my code:

#include <stdio.h>
#include <stdlib.h>

int main(void)
{
 char ch, boot_rom_golden[16];
 FILE *myFile = NULL;

 myFile = fopen("/prj/vlsi/tests/boot_rom_fail/src/apps_proc0/sm6140_rom.a52100000_ROM_FULL.hex", "r");

 if (myFile == NULL) {
    printf("Error Reading File\n");
    exit(0);
  }

while ((ch = fgetc(myFile)) != EOF) {
printf("%x \n", ch);
}

I have two questions:

1. My understanding is if the file does not exist in the above mentioned path, then fopen should return a NULL. Observation is : even if the file does not exist in the above path (/prj/vlsi/....) , fopen is returning some value and then it goes to while loop trying to print the content. Why is this happening? My main.c and the hex file are residing in the same path. But still I tried giving the complete path which also gave the same results (i.e. even if file does not exist it is returning a non zero pointer value)

2. When the code executes while loop, it prints "FF" indefinitely. It should be because of reason stated above.

Please help to know the issue and how to debug these kind of issues ?

Use an int instead of a char for ch

1) Because fgetc returns an int

The C library function int fgetc(FILE *stream) gets the next character (an unsigned char) from the specified stream and advances the position indicator for the stream.

2) Because EOF can be defined as some number not representable by char

Same for boot_rom_golden