arduino mega 2560 using outputs

hi all im new to this forum im wanting some help and advice if possible iv got a mega and want to use all outputs to controlled via 1 input

soon as input is trigger the outputs will start switching on 1 by 1

That is possible, it is a simple task for an Arduino.

Is the input from a button ?
What will be connected to the outputs ?

hi peter

it will be via contacts on a relay then all the outputs would have ematches on them so might have to do a circuit for them

Mega is overkill for that.
Use an Uno/equivalent and shift registers capable of sinking current thru 5V, 12V, 24V, relay coils.
For example, this board I offer can sink 150mA from up to 96 channels, with '328P included for Arduino functionality. An FTDI header is included for serial programming, and then standalone operation.
If you need even more current, the 2nd board can sink 1 AMP from 32 channels at once from high current sources, and even more if fewer channels in each bank are turned on at once. A separate Arduino is needed to shift 4 bytes of data into the card.
Cross Roads Electronics scroll down for schematics, PLs, pricing