Sequence Play mode vs game play mode

As a novice there is something missing in my understanding of how Unreal is working in ‘Play’ mode.
I am creating Cinematics so everything is being driven from my Sequence(s).

I also am trying to Lerp an Actor position from my Level Blueprint with a Timeline Node and a Lerp based on a trigger event from my Sequence.

My question is
Is it sufficient for me to playback my sequence and trigger an event in my Level BP for the Timeline+Lerp to work, or do I also need to enter ‘Game Play’ mode in my Blueprint-Viewport?

And if so, how do I trigger Game Play mode from my Sequence?