Help in passing argu

These are the files avaible in directory
file_1.txt
file_2.txt
..
file_n.txt

how are the command to get the files starting with <file> and how to know the count of total files in the folder.

I am writing a commond and based on number of n Value i want to execte a command, therefore how to pass the argument for file counter.

count=$(ls file_*.txt | wc -l)
./yourscript $count

count is passed as an argument to yourscript.

./yourscript $count