These videos got me started with the Keychain. I've watched them many times to catch what key does what. Eventually certian keys become recognizable.
All these keys are standard and common keys for things like service pannels, lockboxes, Crown Vic cop cars....
Here's the link to the keys:
https://www.amazon.com/dp/B0819XQ9XX/ref=cm_sw_r_cp_apa_fab_-VqGFbMHTB9C3
I have yet to actually use any of these keys.
(Disclaimer: I just think it's fun to own these keys. I do not promote or endorse opening any locks that you don't own or have permission to manipulate.)