Q.Ivy houseplant is sick
My ivy plant, which was previously very healthy, is getting dead branches on it and it looks like it has dirt on its leaves. I have recently moved to a very cold office and had it in the window. Would this affect the plant in this manner?
Please help.

Yes, a change to a different environment can cause stress to the plant.
Inspect the plant more carefully and look for signs of insects.
I suspect spider mites, as this is common on Ivy plants.
Treat the plant with Neem Oil.
Neem Oil is safe for people and pets and will take care of any insects or fungus.
Here are some links to help you.
https://www.gardeningknowhow.com/houseplants/ivy/indoor-ivy-care.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm