How can I loop through a folder containing inputfiles and write outputfiles in a different folder?

I have a bash script that is supposed to loop through a directory (source-folder) and run a program (myProgram) with all files in the directory and write the output to another directory. The files in output are supposed to have a slightly different name.

My myProgram takes 5 parameters:

 ./myProgram   PAR1   infile1.txt   PAR3  PAR4   infile_run1.txt

source-folder:

• infile1.txt
• infile2.txt
• infile3.txt

dest-folder

• infile_run1.txt

• infile_run2.txt

• infile_run3.txt

I can loop through the folder, run my program with all files but my problem is writing the output files into a different directory: Using my code below creates just 1 File named NewName.

How do I get an output file (to the dest-folder) for each input file (from the source-folder)?

#!/bin/bash
for filename in  ~/path/to/source-folder/*;    
do    
	echo  $filename      
	./myProgram -A $filename -B -C ~/path/to/dest-folder/Newname       
done

I was unsure about the features and options of myProgram, so just as a showcase, I created a file called myProgram.sh. Its purpose is to calculate the number of characters in each file and record the counts in the output files:

#!/bin/bash

src="./source-folder"
dest="./dest-folder"

for input in "$src"/infile*.txt;
do
    echo "Processing: $input"
    
    # Determine the base name
    base=$(basename "$input" .txt)
    
    # Construct the output filename
    output="$dest/${base}_run1.txt"
    
    # Call myProgram to count characters in the input file and capture the output
    char_count=$(./myProgram.sh "$input")
    
    # Write the character count to the output file
    echo "Character count: $char_count" > "$output"
done

And the myProgram.sh:

#!/bin/bash

# Count the number of characters in the input file
char_count=$(wc -c < "$1")
echo "$char_count"

for filename in  ~/path/to/source-folder/*; do
    ./myProgram -A $filename -B -C ~/path/to/dest-folder/$(basename $filename)
done

is probably how i would do it though I did not test it, but it should give you something to start on