Question: Can a new USB C dock like this for example:
[USB C dock with Power Delivery](https://rads.stackoverflow.com/amzn/click/com/B07DC25FHC)
be connected and work with an old Macbook (or other USB A gen 2.0 or 3.0 computer) using an adapter like in the picture for example?

[![enter image description here](https://i.stack.imgur.com/Kcmt2.png)](https://i.stack.imgur.com/Kcmt2.png)

If so:
Can I then connect a power adapter, e.g. "Apple 61w usb-c power adapter" or a regular smartphone USB C power adapter to the **PD port on the USB C dock** to deliver power to the dock so as the dock now becomes a **powered usb hub**? (I know it'll not charge the old Mac though. A powered dock/hub is required for more power-hungry devices like several external HDD.)

[I'm concerned that the new dock may damage the old USB A port, especially when the power adapter is connected to the PD port so as the dock tries to send power to the old USB A. For new USB C it detects when the port "wants" to get power and it'll also power the devices connected to the dock along with the computer. The intention with the old Macbook is to power only the dock and the connected peripherals]

Thanks!

Answer: 
The new dock will not damage your old USB A port. USB is backwards compatible, so connecting an USB 3 dock to a USB 2 (or older) system is not going to damage anything.

The old USB A plug does not support what is known as "Alternate Mode" in USB Type-C. Therefore you'll not be able to get the HDMI port on the dock working.

In theory, the USB related functionality such as the built-in 2 port USB hub, and the SD/TF-card reader will be able to function with your converter plug. However, if you connect it to a USB 2.0 computer, you will ofcourse not get USB 3.0 ports or speed on the dock. 

The type-C PD connector on the dock will not enable you to power the old MacBook Pro via the USB A plug, as it does not support the same type of power delivery as USB type-C.

Whether or not the hub in the dock gets powered by the way of the type-C PD plugin depends on how exactly that Novoo hub is designed. I don't think it is likely to work, as a 61W USB-C power adapter is working at 20V (~3A) - while the USB hub inside the dock is usually powered at 5V.
Please do not use the adapters pictured for anything, they violate the USB specification and run the risk of shorting out your power supply. This could be quite dangerous and expensive.

Since your computer has a USB-A port then find a dock with an attached USB-A cable. If you need HDMI output from your dock then there's still options, but they will likely cost more than the USB-C docks because they have more electronics in them to make it work. This is because USB-C supports passing through video natively and USB-A does not. Even if you were successful in connecting the dock with the adapters you've shown, and not start a fire, the HDMI port will not work.

There is a reason the dock has a USB-C connector and not a USB-A connector. This being that the USB-C connector has more wires in it, those wires are needed to support the HDMI output. There are USB-A docks with HDMI output but they will cost at least twice as much because they have a graphics chip in them and this dock does not.

Don't do it.