Two actions at the same time

I'm sure there are a ton of topics on this but I just figured a direct response would be best.

When input digital pin 3 goes high, I want to sound a buzzer for about 250ms and set digital pin 4 high... The problem is that pin 4 won't go high until the buzzer is done. (Cause I'm using a delay) Any suggestions?

Don't use delay()?

Look and 'Blink without delay'?

When pin 3 goes high set pin 4 high and then sound the buzzer.

If your using Tone() to sound buzzer then it is non blocking and you can specify an options duration.

See my Or Robin2's several things at once