I want to optimize the LCP of my gatsby website hosted in netlify

My website is hosted in netlify, the url is: https://www.ennomotive.com/

We are losing everyday visitors due to SEO based on how optimized is the web.

The pages that make us rank the most in SEO are:

https://www.ennomotive.com/open-innovation/

https://www.ennomotive.com/es/innovacion-abierta/

https://www.ennomotive.com/es/ejemplos-innovacion-ingenieria/

https://www.ennomotive.com/es/proyectos-ingenieria-mecanica/

https://www.ennomotive.com/es/innovacion-abierta/

https://www.ennomotive.com/mechanical-engineering-innovations/

I tried some changes based on Page Speed Insights Reports but there are other things that I can´t fix.

For example: "Reduce unused JavaScript"

What can I do with the images? I tried the .webp format but LinkedIn doesn´t support it to preview content is there anyone that I can use?

What would you do in my place?

How would you start?