[time-nuts] Crystal oscillator for a begginer

[Adam Space]

My question is rather open ended. I'm relatively new to timing and whatnot.
So far I have mainly dabbled in NTP, and some GPS stuff with a Raspberry Pi
with a GPS hat. But both of these are limited to timekeeping on an actual
computer system, but I'd like to get into some of the more hardware stuff,
and I figured a crystal oscillator would be a good place to start.

My knowledge of hardware is pretty weak, so I am unsure of how stuff works
in this realm. For example, a quick google search shows very cheap crystal
oscillators, like these
<https://www.digikey.com/en/products/detail/cts-frequency-controls/MXO45-3C-10M000000/1801887>.
But I am confused on how I could exactly use this. One thing I like about
NTP is that I can see and compare different clocks, and synchronize them
to time-scales like UTC, and track their performance over time. But if I
have a crystal oscillator going, how could I compare it or adjust it to
other clocks on my network, or to UTC for example?

Or to take another example, suppose I have a few crystal oscillators like
the one above. Is there a way I could compare them to each other, or log
the offsets from each other, and so on? Ultimately, it would be nice to
compare the frequency and time offsets to a reference source that is
accurate long-term, like my GPS hat Raspberry Pi.

Any ideas, suggestions, or clarifications are welcome. Additionally, if
anyone knows of any guides (either text, video, or whatever), that would be
great too.

Adam