What oil (Break/engine ) do Honda SG 125 take?

What oil (Break/engine ) do Honda SG 125 take? - 1

Read the owners manual
can use Castrol 4T 10W40 in any bike

You seem to be very confused:

Honda has never made an "SG-125". Do you mean a CG-125 or an SH-125?

You don't use oil in the brake system - you use brake fluid.