Just finished my first playthrough! Gotta say this was great as a first instalment - especially with it being your first visual novel too!
Clever to open with a plot hook :) It reminded me of the Scream franchise, with how they open the film with what they want you to believe is the main character, only to kill them off in the opening act! Really gets your thoughts in gear, and sets the tone that nobody is safe.
You introduced us to some fun characters that seem to already have a decent relationship with one another. I'd say take your time a little and let us digest the information given. We don't know an awful lot about Jackson, so litter in little bits of exposition whenever you can.
Loved the artwork on the walls in Jackson's home. They are really well done and look super professional, so big props on that. I also really appreciate the attention to detail in your moving shots. The phone call with Olivia in the car especially, I really liked how you moved the background onwards to show that she was driving and not just parked up.
Overall a really great start. Interesting plot hooks and it's definitely got me wanting to see more. The only thing I'd consider for your next update is to be a little more free and fun with your camera shots. Think of it as filming a TV show, or movie. Give us angles, dynamic wide shots, close-ups etc etc. With it being your first time stuff like that will come, especially as you upgrade hardware and get more comfortable with the programs.
Great job! Really well done. Keep it up because I can't wait to see what happens after that great cliff hanger ;)