How to increase the speed of a website?

The speed of one of my client’s websites is very low. Images are taking much time to load?

Total blocking time = 38ms

Speedex index =20.3 s

What steps should I take to improve it? The URL is https://****
I have used next-gen image formats like WebP.

As you know Increasing the speed of a website is crucial for improving user experience, SEO rankings, and overall website performance. Any suggestions and guidelines in this regard.

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