Think about creating a WhatsApp group for your neighbours or street. And remember that some people are 'off-grid', consider sharing important information whenever you hear it.
There is a Lewisham-wide Covid-19 Mutual Aid group on Facebook which is intended to put people in contact and share information on a wider scale.
Related to this are local whatsapp groups based on ward areas:
Forest Hill https://chat.whatsapp.com/BGzBE202C6cELrzhg2SMFc
Crofton Park https://chat.whatsapp.com/BBw6zHu1G4ZG4F6jJ4njbf
Perry Vale - https://chat.whatsapp.com/GLijgM6K7AyK3pkvfjTVFJ
While major retailers are finding it difficult to keep stock levels replenished, please consider shopping at local independent shops. Many continue to have good stock levels and need the support of the local community to keep it that way.
Similarly, why not consider ordering in a take away from your favourite local restaurants? (and keep your stockpile for another day).