Cyberpunk city, populated, comic style, sidewalk, lots of litter, bright colours. Bing Image Creator.

What is the easiest way to destroy the grass in my lawn. I want to plant a variety of local flowers, grass and ferns.

I don't want to use anything that would harm insects and I would prefer not to take it up in sod because the loam is very thick in rocks.

Would a power tiller work to destroy the grass? Maybe a tarp over the grass?

Thanks in advance.