Any leafy herb you could find starts of - parsley, basil, cilantro, etc.

I'd wait until the heat broke, but leafy greens can be planted for fall harvesting. Leaf lettuce, arugula, kale.

Garlic is planted in the fall.

Dill and cilantro can be easily started from seed. Parsley and basil will do best as plants by now. You can plant kale and heat tolerant broccoli now. You can get tomatoes if you can find good sized plants, but they won't ripen until September. If you are in a warmer zone than I am, you may get a reasonable crop.

Alternatively, turn in some compost or manure and plant a fast-growing cover crop (wheat or rye or something similar) to turn in later in the season. It will help your garden next year.

Thank you!

I have a note to plant spinach by July 26. Johnny's Seeds has a planting calculator based on your zip code. You might need EXCEL to use it. Beets, carrots, lettuce, kohlrabi, Asian greens. I think with carrots you need to read the seed packet and get some that don't need a lot of time to mature. We get a light frost around 9/18 but if I plant bush beans now and provide some protection, I can usually get a crop. I use Agribon fabric for protection. A good garden supply should have it. You would also need wire hoops to keep it up off the plants. There are still a lot of decent looking tomato and pepper plants at certain nurseries. I bought nice broccoli seedlings at Broadway Nursery in Scarborough Maine 4th of July week. I saw a vendor at the Brunswick Farmers Market selling lettuce transplants.