You should post code as a code-section. Take 3 minutes time to learn how to do it with even less effort than uploading a picture
Your code has to be modified to detect the transitions from low to high
if this transition is detected switch on relay and start a timer
check if 3 seconds of time have passed by if yes switch relay off
then check for transition from high to low to reset
The best way to do this is to use a code called state-machine
state 1: wait for IO-pin to change to HIGH
if this happends switch relay on, start timer and switch to state 2
state 2: check if 3 seconds of time have passed by
if this happends switch relay off and change to state 3
state 3: check if switch changes to low
if this happends change to state 1
Here is a tutorial that shows the principle of state-machines