Learning a new coding language

When I start learning a new coding language, I work through the same set of exercises each time. They are my coding kata, problems I know the answers to in several languages now, where the goal is to get the same results each time.

Exercises in ascending order of difficulty:

In a console/terminal window, display the number of days until Christmas this year, or a date that is meaningful to you.
Getting input from the user, display the number of days between two dates.
Write that output to a file, including whether the year you chose is a leap year or not.

Concatenate two user-entered words together, output to a console (string manipulation).
Count the number of a specific letter in a phrase (e.g. “The quick brown fox jumps over the lazy dog” has 3 of the letter e).
Count the number of a specific letter in a phrase entered by the user

Starting from a user-entered number, display “99 bottles of beer on the wall,” counting down to “No bottles of beer on the wall, go to the store and pick up some more.” (loops and control structures)

Display the factorial of a user-entered number (recursion)
Display the cube of a user-entered number
Display the cube root of a user-entered number

Return a true/false for if a given month/year combination has a Friday the 13th.
Count the number of Friday 13ths in a given year (always 1-3, never 0 or 4).
Display which months this year have a Friday 13th, using the system locale for month names (system information, loops).

Get the latest weather data on Mars from https://maas2.jiinxt.com/ (JSON file access and parsing).
Display the latest Martian min and max temperatures in Celsius and Fahrenheit.
Display the current Martian Sol (a Sol is the Martian equivalent of a day).