This book: https://www.amazon.com/dp/1609010019/ref=cm_sw_em_r_mt_dp_YLAIFbH0XZY1D
A Singer or Vogue sewing book or equivalent.
One of these YouTube channels: Evelyn Wood, Fashion Sewing Blog TV, Lifting Pins and Needles.
A Craftsy subscription? They have a beginnner package.
In terms of Free, do check out two YouTube channels that specialise in round-ups: Alisa Shay Thoughtful Creativity and And Sew On.
I would recommend getting a generalist sewing book like the Vogue or Singer sewing books. Burda (DE) and Alison Smith (UK) also have books.
One book that is based on a course outline from a design school is https://www.amazon.com/dp/1609010019/ref=cm_sw_em_r_mt_dp_YLAIFbH0XZY1D
I would still recommend Big4 patterns, just remember that Finished Garment Measurements are Your Friend!
But, overall, I think it's best to a) sew a project you want to wear, regardless of actual/perceived difficulty and b) learn to break down projects into skills (sew a straight line, sew a casing, insert elastic, sew a dart, put in a zipper, sew a buttonhole etc.) than to rely on instructions every time you start a project UNLESS there's a tricky bit like a twist/knot, overlapping pleats etc.
PSA Your local library needs love too! Good luck!
The pants waistband is a method of construction with trim. I recognize it from the "tailor waistband with sateen trim" part of my favorite, most useful sewing book ever a guide to fashion sewing