@marvellousmaple You can get bay window poles and have curtains. The issue is it’s a wide bay so once the curtains are opened you’d have quite a lot of material bunched up at either side, although you can also get poles that wrap around onto the side walls so you’d push your curtains there.
A pole like that with 5 bends – the two inside the bay then the outside corners – would be quite expensive if you want it to have a pair of curtains that can open to the sides. A cheaper option is either a track – you can get them that long and they’re bent to shape in situ using warm water – or a curtain pole that’s fixed at the inside corners: here, you’d have a curtain on each of the left and right hand windows, then a pair in the middle, so when open the curtains would hang in four parts: outside the bay, and two hanging between the windows.
You can also get double poles if you want to have voiles that hang in place on the inner pole for privacy, then the outer pole holds the curtains.
John Lewis does MTM bay window poles but they’re about £500. A Screwfix track is about £30.
Cheaper yet and maybe less faffy than curtains would be a Roman or roller blind on each window in the bay: try blinds2go or other cheap online MTM options.
Pinterest is your friend here, just search for bay window treatments.