TeamViewer can be used to provide remote (over the internet) technical assistance. It’s secure and cannot be used without user permission.
Zoom supports voice and video chat over the internet.
Downdetector will give you an indication if a common website or service is available or having difficulties.
haveibeenpwned? will show if your email address has been compromised following data breaches.
Get Safe Online provides some really useful advice on how to stay safe.
UK Gov NCSC highlights some of the best, most useful guides to protect you, your family and your business.