how i can make on oracle hot backup?

Answer 1

If you're running a new-enough version of oracle you want to use the 'rman' component... or if it's older then you may have to pay for rman as an extra-price product.

Otherwise select every tablespace into hot backup mode, checkpoint 'em, back up the data and the archive logs and the control files.

If that is greek to you, ask a DBA to do it for you... cos if you get it wrong you can trash your database.