Undefined functions in header file - c

Question

I am trying to create a sudoku solver and want to divide my project into different files.
I want my board.c file to handle the creation and printing of the board while the solver.c file will have the solver functions and such.
I currently have three three files. sudokuSolver.c, board.c, board.h
Have I defined the header files incorrectly or am I missing something else?
sudokuSolver.c:
#include <stdio.h>
#include <stdlib.h>
#include "board.h"
int main()
{
int** board;
board = createBoard();
printBoard(board);
free(board);
return 0;
}
board.h:
#ifndef BOARD_H_
#define BOARD_H_
int ** createBoard();
void printBoard(int**);
#endif
board.c:
#include <stdio.h>
#include <stdlib.h>
#include "board.h"
int** createBoard(){
int array[9][9] = {
{3, 0, 0, 6, 0, 2, 0, 0, 4},
{0, 0, 0, 0, 7, 9, 8, 0, 3},
{0, 1, 0, 0, 0, 0, 7, 0, 0},
{0, 0, 0, 0, 6, 0, 0, 0, 2},
{0, 4, 1, 7, 0, 8, 0, 0, 0},
{7, 0, 6, 0, 0, 0, 4, 0, 0},
{9, 0, 7, 2, 8, 5, 3, 4, 0},
{0, 8, 0, 0, 0, 0, 2, 9, 0},
{1, 2, 3, 0, 4, 7, 5, 6, 0}
};
int k, **board;
board = malloc(9*sizeof(int *));
for(k = 0 ; k < 9 ; k++)
board[k] = malloc(9*sizeof(int) );
for (size_t i = 0; i < 9; i++)
{
for (size_t j = 0; j < 9; j++)
{
board[i][j] = array[i][j];
}
}
return board;
}
void printBoard(int** board){
for (size_t i = 0; i < 9; i++)
{
for (size_t j = 0; j < 9; j++)
{
printf("%d ", board[i][j]);
}
printf("\n");
}
return;
}
EDIT: When I try to compile the code with gcc sudokuSolver.c board.h board.c in the terminal.
After compiling I now have an executable a.exe file that runs the program correctly.
Now I run into a new problem. After the code is compiled I try to run the code directly from Visual Studio Code (Ctrl+Alt+N) But still receive this error:
C:\Users\x\AppData\Local\Temp\ccbnvRga.o:sudokuSolver.c:(.text+0xf): undefined reference to `createBoard'
C:\Users\x\AppData\Local\Temp\ccbnvRga.o:sudokuSolver.c:(.text+0x1f): undefined reference to `printBoard'
collect2.exe: error: ld returned 1 exit status

Answer 1

As Some programmer dude pointed out. I had to configure VSCode to be able to compile multiple source files.
I solved this by adding
,
"code-runner.executorMap": {
"c": "cd $dir && gcc *.c -o $fileNameWithoutExt && $dir$fileNameWithoutExt"
}
in settings of the code Runner extension