Delay timer - variable with a petentiometer

Hi guys, I'm very new to arduino, I'm in the mechanical field and just started playing with Arduino to automate a few projects. This is where the issue is. I've just started learning about Timer functions as I'm trying to make something do the following:

when one event happens, i want it to trigger another event to happen, but i want this event to be delayed, but i need that delay time to be adjustable from, say, 1 to 30 seconds, by a potentiometer. But i need other events to happen in the meantime (ie the first event continues to happen).

so for example:

flick a switch, and relay one powers up straight away, then a timer counts down (to a value set by potentiometer), then once the timer reaches zero, relay 2 powers up. they both stay powered up until the switch is switched off. The switch will eventually be sensors, but at the moment it's a switch. I've though about using multiple arduino units, but I'm sure it can be done easily with one unit.

this will be used in multiple places with slightly varying functions so so in some instances there will be multiple relays with different time delays, and they all need to be adjustable via different potentiomters.

this way, i can tune the whole system to maximum production rates by simply turning a few potentiometers.

can anyone help me please?

You need to write the code as a state machine. See my
Or Robin2's several things at once

Thank you, I'll read it all tonight and see if i can get this working. I appreciate your time to answer me.