Relationships between instruction execution and clock cycle in modern CPUs
The five bullet points you mention happen simultaneously, executed by the different units of the CPU.

They are just "triggered" by the clock cycle; then they reserve that unit for as long as they take. Most of these operations just take one cycle, so that the every clock cycle the whole processing pipeline "moves one step forward". 

But, for example, if an operation (e.g. fetching from RAM) takes multiple cycles, that part of the processor simply is blocked for that long. The others will, in the meantime, continue to do their work – as far as that isn't blocked by the blocked unit.

In your case, the add instruction simply takes one cycle to execute; it will have taken multiple cycles to be fetched from RAM, a cycle to be decoded.