hi all , i am trying to read a string from user in TASM assembly , i know i need a buffer to hold the input , max. length and actual length , but i seem to forgot how exactly we declare a buffer

my attempt was smth like this

Buffer db 80 ;max length
       db ?  ;actual length
       db 80 dup(0);i think here is my problem but can't remember the right format

Thanks in advance