You can use a timeline plugin, but I just have a cutscene variable. Cutscenes are a little complex to make, but not terrible if you break it down.
At the start if when the cutscene should begin, I set cutscene = 1. I then use that variable to measure the progress.
If cutscene = 1
---->Trigger once, do stuff, wait 3.5 seconds, set cutscene = 2
---->Every tick, do whatever.
Then repeat for each "phase" of your cutscene. I have the main event and then two subevents (the second is unnecessary, but god for organization) to accommodate the things that wil happen continuously (camera movement, character movement, fades, etc.) and things that happen once (triggers, spawning/creating objects, destroying, setting variables, playing sounds) with a wait to let the game know how long that segment should last. I then repeat the process for each segment of the cutscene. At the start of the cutscene, be sure to disable character controls and/or start ignoring input.
You can get as complex as you'd like, as you can imagine, but that's th gist of how I do all of my cutscenes.