The article mentions help being available, but what really does it recommend if you do have long-covid? Everyone knows vaccines and masks help, but there seems

The article mentions help being available, but what really does it recommend if you do have long-covid? Everyone knows vaccines and masks help, but there seems to be remarkably little being studied about dietary habits/supplements/physical activities that might aid before or after covid. Anecdotally, my brain fog was lifted pretty quickly once I started taking vitamin D and B-complex, which I just took on a hunch, but I honestly have no idea if it actually helped. Does anyone know of any larger-scale data collection efforts?