Hi there,
It isn’t necessary to change themes if you like what you are using. If you want to switch, you can simply download and activate Dyad 2.
However since you have a child theme, you likely have customizations that will need to be added to a child theme of Dyad 2.
If your host offers a staging environment, you can do some testing and prepare your Dyad 2 child theme there.
Here’s a prior thread explaining the differences between the two themes, so that you can decide if it is worth the switch.