Welcome to the forum.

The BOR, or in the case of the 16F876A, BODEN is set in the configuration bits.
Go to the PBP directory and you will find the *.inc file for all of the chips supported by PBP. You can set the configs there or in code space.
http://www.picbasic.co.uk/forum/cont...o-your-Program
The above link walks you through it.
The 16F876A only has two options, BODEN_ON or BODEN_OFF.