adjust the valves- the clearance between the rocker arm and the valve should be checked with a feeler gauge.
stop using cheap or the wrong grade of gas. use fuel injector cleaner and octane booster and that should do it.
The lifters are failing and need replaced to stop the noise.
yes horn is not working
clock spring
clock spring
Check your EGR valve
Sounds like the porselin Valve!!!!
PCV valve.
May be the Idle Air Control Valve sticking or dirty.
stop noise become wise
The duration of Stop That Noise is 420.0 seconds.
Fixing or replacing damage parts. You can try heavier oil. 10w40