Do players resolve each attack first before moving onto additional attacks within an action?

Question

The scenario is I have a level 6 fighter in 5E that has two attacks per Attack action. When there are multiple targets (say 2 orcs) and he wants to attack, he feel that PHB states he would announce his action to attack. Do his first attack and see what the result is, then decide how he would use his second attack.

He wants this to avoid 'wasting' attacks. If the first attack killed the first orc, he would then use the second attack to kill the second orc.

How I read it as the DM is you announce what your Action is during combat on your turn. Then if you have multiple attacks, you indicate which each one is doing. Then you roll for each attack in the sequence you are doing them.

Example:

He wants to attack both orcs. He would roll to see if he hits the first, then the damage and then he would roll to see if he hits the second and then damage regardless if the first orc dies. I would indicate once his Action is complete what the results are.

Can I please get feedback as which way makes more sense? I am arguing that you have 6 seconds for your turn and hitting a target to see what the results are before doing your second attack is not possible within 6 seconds.

Answer 1

The Fighter gets to declare and resolve each attack severally, as he likes:

This follows directly from the "Making An Attack" section of Chapter 9: Combat.

Whether you're striking with a melee weapon, firing a weapon at range, or making an attack roll as part of a spell, an attack has a simple structure.

1. Choose a target. ...

2. Determine modifiers. ...

3. Resolve the attack. ...

This three-step sequence happens for each of the lowercase-a-attacks provided by the fighter's Extra Attack feature when they take the uppercase-A-Attack action. If you look very closely at lowercase vs. uppercase attack/Attack usage in the PHB, it's actually really consistent and informative. And nigh-impossible to notice!

Answer 2

this also makes sense as you can move between (small a) attacks.

So for that capability to make sense you would have to completely resolve one attach before (literally) moving on to the next.

Including any possible attacks of opportunity.