Herbs and lettuce are lovely, but you're never going to feed your family on them. You need to grow bulky staples such as potatoes, onions, broad beans, beetroot, peas, brassicas. If you plant EARLY potato tubers now, you will get a crop this year. 'Early' means fast maturing, rather than that they can only be planted early in the season. Another staple you can plant now is the winter brassicas, such as kale, purple sprouting broccoli and cabbage, but you would at this stage have to send off pronto for small plants - advertised by all the seed companies, and available in garden centres. It's an expensive way to do things, but it's too late to sow brassica seed now. If you can find courgette or well grown squash plantlets, get a couple each of them in too.
You might get away with quick maturing peas.
I'm afraid the only way you will keep your cats off the veg patch is by fencing it effectively, or covering everything with horticultural fleece or chicken wire. From their point of view, you have provided them with a perfect toilet, with soft, cultivated soil to be easy on their paws. I'm sure they're really grateful. But not only is it yuchy to eat food from ground where cats (or dogs) have crapped, but they carry parasites which affect humans, sometimes seriously.
Maybe you would be best preparing your large veg bed for next year, and researching how to go about things, so you're well prepared to start then. Growing veg is hard work - it's not just a case of sowing and planting; the main job all year is weeding
to get any crops at all. Potatoes are the traditional crop to 'clear the ground', as they need several earthing ups, so the weeds are destroyed then, and they have to be dug out when they are ready.