It’s always best to start with your intended use, but let’s break that bundle into two halves to see if that makes it easier.
The low frequency portion is the xEM implant, and the xAC controller. These are useful together if you want to open something that you have built / control. This is a good example of what you could do, also useful for homemade house door locks.
The high frequency portion is the xSIID, and the keyboard reader. These are useful together for electronic logins on PCs and such. An example is HERE.
You can also clone the xEM to duplicate some older style (but still in use everywhere) RFID key cards. Think work badges and such.
That should be enough to get you started. If you come up with something specific that you want to do with your implants, then let us know and we’ll all try to get you headed down the right path. There’s some wicked smart people floating around here, and they’re all pretty helpful if they can be.