If my opponent rolls say 2 surge on an attack but no damage does he get to use surge to cause damage? I swear I read that if no damage rolled no surge damage can happen just can't seem to find it. Sorry if this has been explained I searched the forums and couldn't find anything to clarify

Damage from surges and "native" damage are combined to determine the damage done to the target. In this, there is no difference between surge damage and native damage.

However, some effects triggered by surges need at least one damage done to the target, e.g. bleed or stun.

What DerWombat said...

Any conditions , including beneficial ones (focus) require 1 damage to get through. Also keywords like Blast and Cleave require the damage to get through first. Things like 'Recover', 'Pierce', '+ Damage' and the heroes' ability to remove a strain via a surge (in campaign) do not require the damage to get through.

Just remember that "surge: +1 damage" does not mean you inflict a free damage on the target, it just means you get to pretend one of your attack dice had an extra damage icon on it; if the target rolled dodge, or rolled enough block, the surge:damage still might not do anything.

Also, if you don't have a surge ability that says +1 damage, you can't use a surge to do more damage.

Special Situations Regarding Attacks (RRG pg 6), 6th point:

The keyword abilities Blast and Cleave, and any keyword that causes a condition, all require the target of the attack to suffer one or more damage to trigger.

To answer the OP question; you may use a surge to add extra damage even if the damage icons on the dice don't deal damage.

For example, You roll 2 damage and 1 surge, and your opponent rolls 2 blocks. You can use the surge to add +1 damage and deal 1 damage to the defending figure.