Video and Audio Calls
There are a number of services available which enable you to talk with friends and family using your computer, smartphone or tablet. In most cases, free services are available with additional features or capacity available for paid subscriptions.
Skype is available on PCs tablets and smartphones either via an app or via a web browser. To use Skype, you (and the people you call) need a free Skype account. You can contact people using their Skype username or their email address
Zoom is available on PCs tablets and smartphones either via an app or via a web browser. To use Zoom, you create a Zoom Meeting and then send a link or passcode to people you want to talk to.
Facetime is only available on Apple devices. To use Facetime, you need an Apple account and need the account name, email or phoen number of the person you wish to call.
Other video call services
There are a number of services now available, eg Facebook Messenger, Google Hangouts, WhatsApp. Your choice depends primarily on which one you and the person you wish to call prefers to use.