I'm a total beginner.

For your first project, the best combination is medium-weight yarn paired with medium-sized needles. This makes the stitches easy to see and handle without being too bulky or too fiddly.

Here is what I recommend for a beginner:

• Yarn: Look for "Worsted" weight (often labeled with a number "4" on the yarn label). Choose a light or solid color, as it is much easier to see your stitches compared to black, dark blue, or variegated (multicolored) yarns. A smooth wool or acrylic blend is generally best; avoid "fuzzy" or novelty yarns, as they are very difficult to undo if you make a mistake.
• Needle Size: Look for size US 8 (5.0 mm). These are the standard size for worsted weight yarn and provide a comfortable grip for a beginner's hands.
• Needle Material: Start with bamboo or wood needles rather than metal or plastic. Wood has a bit of "grip," which helps prevent your stitches from accidentally sliding off the needle while you are still learning to control your tension.

A quick tip: When you buy your yarn, check the label for the "suggested needle size." It will usually list a range; choosing something in the middle of that range is a safe bet. Have fun getting started—knitting is a wonderful skill to learn!