There are mainly two types of chargers for Mac or Mac Pro: 

Original chargers: MacBooks typically use USB-C chargers as the original charging option. These chargers are designed by Apple and come bundled with the MacBook when purchased.

Third-party chargers: MacBook users can also use third-party USB-C chargers that meet the required specifications and standards. It's essential to choose reputable third-party chargers to ensure safe and efficient charging for your MacBook.

No, it is not recommended to charge your Mac with just any charger. MacBooks require specific chargers that are compatible with their power requirements and port types. Using an inappropriate charger may not provide enough power or could potentially damage your device. Please always use the official Apple MacBook Pro charger or a certified replacement like Anker Charger 747 to ensure safe and efficient charging.

Yes, it is typically possible to charge a MacBook with an iPhone charger or chargers for iPad if they have USB-C connectors or you use appropriate Lightning to USB-C adapters. However, note that this method may deliver less than ideal charging speed if the wattage of your iPhone charger is low.

It is generally safe to leave your Mac charger plugged in when not in use. Most quality MacBook chargers are with built-in safety mechanisms, including overcurrent and overvoltage protection, to prevent any potential damage or hazards. However, although this practice is not hazardous, it might reduce the battery’s charging capacity, and hence not generally recommended.

To properly charge your Mac, follow these guidelines:

• Use the original Apple charger or a reputable third-party charger specifically designed for your Mac model.
• Plug the adapter into the power outlet.
• Plug one end of the charging cable into the charging block.
• Plug the other end of the cable into your Mac's USB-C or MagSafe port, depending on the charger type.
• Wait for your MacBook to charge fully and unplug the cable when charging is finished.