Anyone wanting to learn how to cut complex roofs, stairs and other advanced carpentry should get a construction calculator and the book "A Roof Cutters Secrets". It is one of the best books i have found and will up your game as a carpenter.
Hey man I think I was in the exact same spot a few years ago, here's a book that has helped tremendously and continues to.
https://www.amazon.com/dp/0945186061/ref=cm_sw_r_cp_apa_glt_fabc_P03G5JX5QKZYQ53M079J
Old school carpenter and he explains everything. Framing all kinds of weird shapes and what not. Can't recommend it enough.
Metric isnt really helpful in the USA. Helps to be able to do fractions in your head. Plumb, square and level are the holy trinity. Learn to use the speed square and how read a tape if you want to frame houses. The "Roof Cutter Secrets" is one of the best books on carpentry I have seen in 30 years of banging nails. It is only about layout. How to layout basicly any stair, roof, arc, rake wall, etc by using a construction calculator. Seriously, master the calculator and you will always be employed.
Yeah, that's good stuff. But it doesn't always pertain to good carpentry practice.
Look up;
A Roof Cutter's Secrets to Framing the Custom Home https://www.amazon.com/dp/0945186061/ref=cm_sw_r_other_apa_i_KBApFbXY7NB1X
Or
Carpentry and Joinery Book 2 by David R. Bates (1986-11-19) https://www.amazon.com/dp/B01FKWOD96/ref=cm_sw_r_other_apa_i_iDApFb7VZ3ATM
Please note that these are classics and the subjects covered, principles addressed, and lessons taught will always pertain to the current jobsite.
IF you're trying to learn something, skip Larry Haun. He's interesting and it's a nostalgic watch, but he didn't build with today's methods. listen to his audiobook for leisure, but to get up to speed watch these youtube channels:
gregvancom - nerdy guy with excellent sketchup animations
MattBangsWood - humble dude using today's methods. start with this video
Matt Risinger - good notes on building science. He's clearly sponsored by Huber.
The Honest Carpenter - another humble dude. Start with this video
Perkins Brothers - they do foundations too, which is nice.
Framing Beast - wears a go pro and moves fast. Some of the other channels are a bit cutesy, this dude is actually getting work done.
Fine HomeBuilding - has some good info, if stale. Their series on Deck Construction is up to snuff.
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If you want to learn to cut a roof, this book is it: A Roof Cutter's Secrets