Here's a closeup shot of the plant.

IT IS MORE THAN "a" PLANT. There are about half a dozen plants in there. It is ok to have two of them together but not 6 or 7 of them like that.

I would try just pull out the 3 small ones on the RIGHT/FRONT. Then divide the rest into TWO groups. Then plant them either in separate pots. Or you have big pot , space them abot 10 inches. Plant them slightly deeper, add little bit more potting soil around the stems and gently pack it .... FERTILIZE !

Those SWEET BASILS can get quite large, if well taken care of and planted in larger pots. What you see now are just seedlings.

If you are referring to the browning of the base of the stems as 'dying', don't worry. That is what basil does. The stems become woodier at the bottom.

However the leaves look as if they have spider mites. Also the soil looks very dry indeed. They need to be outdoors.

You can grow basil in clumps if you live in a cooler climate and don't expect it to grow into a bush. You can treat it as a cut and come again plant like lettuce. But it does need water. The photo shows basil grown like this.

Planting basils in the clumps, in cool weather ???

Now our daytime temps are in high 70s/ low 80s F, my basils are still struggling. I am growing 5 different kinds. I cannot imagine growing basil in COOLER climates. Unless they have bred some different kinds. Those CLUMPY basils in 6" pots,are sold in the supermarket for kitchens. You buy them clip them, ..they die. Good bye.

Yes - seysonn. I never even attempt to grow Basil outdoors here. Some people try but it is often a runty failure. I just grow a crop of cut and come again in my greenhouse. I sow my own, never buy it. Just one type. At the moment the temperature is in the 80s. That is extremely unusual for us and is classed as an amber alert heat wave. Usually the temperature would be in the 60s - low 70s. Plus we get lots of overcast skies and rain.