For a few days after a chemo infusion, there are honestly days when you don't even want to swallow a sip of water. When you listen to women going through gynecologic cancer treatment, one line comes up again and again: "Just the smell of rice cooking turns my stomach." But if you skip meals altogether because nothing appeals to you, your strength bottoms out, and sometimes your next treatment date even gets pushed back. So in the stretches when you can barely eat, "what and how you eat" actually matters quite a lot.
For now, it helps to set aside the idea of eating a lot in one sitting. When you have no appetite, even looking at a big bowl of rice feels like a burden. It's far easier to put a little into a small dish and eat often, every two to three hours. Cooled food is often easier to take because it smells less. If the steam and smell of freshly cooked rice bothers you, try letting it cool a bit, or switch to chilled porridge or a cool tofu dish.
During treatment it's easy to lose weight, and if you miss out on protein at that point, recovery slows down. To get protein in without it feeling heavy, things like steamed egg, soft tofu, white fish, or gently cooked chicken breast work well. If you struggle with milk or soy milk, you can sip a grain-powder drink (misutgaru) or a protein drink a little at a time. Honestly, adding one more spoonful of protein at each meal ends up sticking with you better than any elaborate "restorative" feast.
If your mouth is sore or feels dry, keep harsh seasonings at arm's length for a while. Spicy, salty foods and sour fruit make the sore spots sting more. Instead, lukewarm broth, softly mashed potato, or pumpkin porridge go down easily and help. Even so, when nothing appeals to you at all, it's surprisingly handy to know one or two of your own "appetite switches" that get the saliva going, like a chopstickful of tangy seasoned radish or a sip of green plum tea (maesil-cha). On days when the nausea is bad, though, it's better to focus on at least sipping fluids often rather than forcing food down.
And one thing people surprisingly overlook is the atmosphere. Rather than eating alone, zoning out in front of the TV, there are days when sitting down with family even briefly gets one more spoonful in. Feeling a little hungry after a short walk is a good sign too. That said, anti-nausea medication and nutritional supplements suit different people differently, so if there's something new you're thinking of taking, I'd suggest talking it over with your care team before you start.
What's written here is only general advice on eating, and the approach that suits you will differ depending on your physical condition and the stage of your treatment. If the confusing days or the days when nothing will go down start to drag on, don't struggle with it alone, be sure to ask your attending doctor or a dietitian.