Hello

How can I create a text file by using dos commands?

I am trying to use echo command such as
echo Hello > test.txt
echo Hi, how are you? >> test.txt

But, the echo doesn't put any null terminator at the end of string.
When I check the string length of each, it should be 5 for Hello.
It is not, it become the length of buffer that read the line.

Anyone, please give me a suggestion.

Thank you.
Pong