Saving data on arduino

Hello, everyone. I am doing a fever detector for accessing to public establishments and I am using a non-contact temperature sensor and an LCD which indicates the value of temperature, but I have a problem. I want to save all the values with its respective dates. I am also using a RTC to indicate the time on the LCD so, can someone help me with this? I just want to know how to save the temperature values on a memory.

you could use a MicroSD card adapter for that.
There are plenty of modules and tutorials available!
Does this help guiding you in the right direction?

There are 3rd-party Arduino-compatible data-logger boards which already have an RTC and (micro)SDcard socket built-in, for instance the Seeed Studios Stalker is an example.