Obviously things like soup, or ramen noodles and other hot liquid meals don’t taste good at all cold.

You don't have to have them cold - just get a flask!
There are many good affordable flasks on the market today, OP might even have one already, but they might need more than one.
In the flask you can not only put things like soup or even pasta with sauce, but also just boiled water which you can later pour in to a pot noodle and have a fresh one of those! Or a hot cup of something (tea, coffee, cocoa), made with the water in the flask, or in their own flask! The options are endless.
If they have access to a microwave/hob in the morning they could even pre cook some hot dogs or other protein (meat or plant based) that would fit in, dump it in along with a preheated tin of sweetcorn or peas and maybe even tinned potatoes, some seasoning (a tab of butter/margarine like hotels serve would do wonders), then keep it warm in there for the rest of the day.

Another alternative if they really want hot food would be one of those thermal bags, but in my experience they don't do as good a job at keeping things hot (warm maybe, but nothing more).