San,
Strictly speaking, you cannot convert a .csv file to an .mdb, because
whereas a .csv file contains only some (comma separated) text, an .mdb
file is much more than that. What you can do, is import a .csv file into
an Access. That is done from within Access, with the .mdb file open; go
File > Get External Data > Import, select Files of Type: Text Files
(*.txt, *.csv etc), locate the file you wish to import and follow the
import wizard instructions. If this is going to be a regular process,
you could create a macro or VBA procedure to automate the task.
HTH,
Nikos