Q.Question About Zones For Foxglove
I am in zone 9, you said foxglove are good in zones 3-8. Does that mean I may not have much success? This past spring was my first time planting them. The sellers website said this one is good in zone 9. I got bare roots on delivery. One plant sprouted flowers and they were beautiful. It actually got flowers twice! Another one grew beautiful leaves. Now we come to winter and it’s colder than normal (mid to high 30’s). If they do come up again, do they do well in the heat if they are in the shade! Thanks.

Certified GKH Gardening Expert
They don't seem to mind how cold it is. They don't do their best in the heat, but shading them in the shadow will, certainly, help. Many cultivars are suited for zone 9, but most are for zone 8 and below.
Keep in mind that this is a biennial. It will only come back for tho years.
https://www.gardeningknowhow.com/ornamental/flowers/foxglove/foxglove-winter-care.htm