Carpentry is a great skill to learn. Observe carpenters at work, and read “how to do it” websites. This will show you the basics.
Accumulate some hand tools, and a good tool bag or apron. Always remember, “safety first”.
I found this book indispensable, and keep a copy around so the ideas are fresh, especially on layout and project planning:
Consider going to a school, or joining an apprenticeship program.
This is one run by a community college in the US: Registered Apprenticeships
This is a good guide to keep in your toolbox:
Keep in mind that carpentry is a craft that takes years of work and practice to master, learn all you can, and you will do famously well!