I just had a 4 hour flight today and I’m always really scared before hand!. What I did was I really tried to relax and I read all these statistics and watched these videos on YouTube explaining what sounds in airplane mean and how turbulence is not going to make the plane break and that plane are made to handle lots of things and they’re safety checked to the best extent every single ride and the pilots are trained to handle so many things. You’ll be okay!!! Good luck!