Be able to identify different wood types by color (Oak, Pine, Cedar, etc.)
Know the “nominal” lumber dimensions and what they look like (2 by 4, 4 by 4, 2 by 8) etc. I think 2 by 4 is the most common for building houses. You should be able to call out a piece of lumber just by looking at it. Extremely important for working with others.
Funny Twin Peaks clip about lumber dimensions: tiktok.com/t/ZP8UWJ3bq
Learn how to use these 5 types of power saws: Mitre saw, table saw, jig saw, reciprocal saw, circular saw.
Practice cutting lumber AND plywood with the table saw and jig saw. Practice cutting lumber with the mitre saw. Use sawhorses for long pieces.
Practice routing with a drill router bit. Practice drilling + screwing. Practice hammering and nailing. Practice using wood glue (with clamps). Look up the types of wood joints and practice the most obvious and basic ones (butt joints, dado joints, etc.) (you don’t really need to memorize the joint names, I think nobody does).
Learn sanding, especially for wood joints that aren’t flush. Try practicing with both power sanders and by hand with sand paper.
For finishing furniture, learn to sand it down AND apply polyurethane.
Chiseling is a helpful skill but not super important. I've only ever used it for installing door knobs and door hinges.
Not necessarily woodworking, but if you ever plan to do house work you should know how to cut, paint, screw, and spackle *drywall*
Don’t practice these aimlessly. Build something useful and practical. That’s how you stay motivated. Run a cable through the studs in your house. Build a bedframe or a table. There are millions of useful schematics and videos online showing you how to build basic furniture. It’s not a crazy skill, anyone can learn this as they go.