I want to do "off" delay or something like it.

Hello, the reason i start this topic is simple because i cant find solution to my problem. What i want - to create a delay, timer, stopwatch etc. anything similar that will allow the following to happen: When i click Button #1 (attached to pin 8), this special delay starts counting up to 20 seconds. If within these 20 seconds i click Button #2 (attached to pin 7) then light up a LED for 5 seconds (connected to pin 13); But if within them i click the Button #1, the special delay stops, the LED turns off and the code detects if i would click it again to activate the special delay. But if i click Button #2 before the special delay has started, nothing happens.

And if this is impossible, atleast tell me how to insert delay that doesn't stops the whole code but simply a single "block" of commands.

JMD1: tell me how to insert delay that doesn't stops the whole code

In the IDE, look at File > Examples > Digital > BlinkWitOutDelay

Pretty straightforward. Use millis() to remember when button #1 is pressed and a flag to know if special delay is active.

You have not described what will happen if button #2 is pressed at the end of special delay. Will it stay lit for 5 seconds or will it turn off at 20 seconds when special delay end? Also, if you press button #1 again without having pressed button #2, will special delay end or should 20 seconds timer restart?