bash - Is there a way to group parameters into command in Linux? -

i know in linux can this:

$> cat file.txt > total.txt

and understand following same thing:

$> cat < file.txt > total.txt

as cat copies whatever in stdin stdout

so wondering if following:

$> cat file1.txt file2.txt > total.txt

can done in way :

$> cat < file1.txt file2.txt > total.txt

but turns out file1.txt redirected cat there way " parenthesis" group parameters of cat or other command ?? in :

$> cat < (file1.txt file2.txt) > total.txt

if there txt files

cat *.txt > output_file

any limitations using this? or did wrong?

Shell