It is nice to have a pub half way round on a full day walk and have a chat with the locals and bit of local information, but these days and the struggling pub trade, I've often found them closed. Though I do try to research the villages/pubs to see if they will be open. But if it's closed, I usually find a local shop in the village where I can buy a beer to have with my lunch before heading back.
I often have my lunch in a thermos, such as sausage and beans, ravioli or a pot noodle and a couple of slices of bread. That said, if I find a pub at lunch time and it's not too packed, I often end up bringing my lunch back with me and have it when I get home.
Walking with Covid may mean a change or two. But they way I walk, I don't think it will be too much of an issue for me. Though I could start to carry a beer with me for lunch, but that would mean drinking a warm beer uuuh.