Firstly, be minded that this forum is not a dating agency.
Second, surely you realise that car sharing with strangers is currently out of the question.
But, if your search is genuinely for walking company, I suggest you join Ramblers. Ramblers official walks are still permitted being considered 'organised exercise/sport'. There will almost certainly be a group near you. You will have to make your own way to the start of the walks and currently we should all be staying local anyway. Check out Ramblers website for details.