Hi @Nemo 32 !
Thank you for asking and welcome aboard! Here are some great tutorials that should be able to get you started in the right direction.
Download & Installation Help:
Article: ImpulZ - How to use the Library
Video: Using ImpulZ with Adobe Software
I know you said you're working with Davinci Resolve but I think the main complexity of ImpulZ comes not from the grading software but the layering of the LUTs. @Dave Andrade34 did a great job explaining how to combine the LUTs in this video and it's worth a watch just for that.
Video: How to use ImpulZ in Davinci
And here's a more practical tutorial on how to apply the LUTs in Resolve.
I've only included tutorials for ImpulZ because it's the more complicated library to use and usually causes the most confusion for new users. OSIRIS is much simpler. You'd simply pick an OSIRIS LUT that you like for the color space of your source footage (Rec709 for standard video, LOG for professional, flat-looking video optimized for post production) and apply it to a corrector node in Resolve. When you get more comfortable with the LUTs and find a workflow you can start to creatively combine LUTs from both libraries to build your own looks.
Anything else and we're here to help! :)