comments:
The letters and first numbers are just a naming convention (so an "H" hook should generally always equal an 8 hook or a 5mm, but sometimes I see weird hooks that don't quite match). I think a lot of hooks default to just using millimeters these days. (And the millimeter number actually refers to the width of the hook). I'm a big fan of grabbing a set like this (notably, a set with bigger handles). It gives you a lot of sizes of hooks to play around with, and I find crocheting with those small metal type hooks (like the ones in your pic) to be more frustrating, especially with the small sizes. https://www.amazon.com/MECHEER-Beginners-Ergonomic-Arthritic-Crocheters/dp/B0C33QM3KR?crid=3LEO1YOWS3ISX&dib=eyJ2IjoiMSJ9.X-CALXh4V0sJ6SQrKskPYWTLDPCeTBAZ9-4v20pJBnD4kkSn3fOh2nSVIqtqFATA-rpgf7L6TzZsC0u7vA77j-jSo4m9AApAViidQkf81EyAylwFF4EqwO-SBafmYRcxNzTSEtSZ1L0fHQdWB7AX5XrqhxYI13OxbABQkEqtQc5VPsqpquTxeKc6AXO0K425_D1VSeUnEW1b5xPtIhLpR5nZjJ0zfgZyzGl6cg85wExKoAeiJ9c6mla02W02KTztQo7U9j6oUo7Lydtl4hHH37lhzYHRZdIV6BG5pZCCN9s._gzW5yiV5l-eZHfsCukTZP-gu0X4Trh-4atbRr3aCXo&dib_tag=se&keywords=crochet+hooks&qid=1781714239&sprefix=crochet+hook%2Caps%2C165&sr=8-7 If you're making something to wear, sizing is important, so it can be nice to have a range of hook sizes- then if your hat width (for example) is too small with one hook, you can go up a size of hook so it will be wider. If you're just beginning and want to just use the hooks you have, you can search patterns by hook size. But again, for wearables, it can get more tricky if you need to scale up or down. Scarves can be a great beginner project because sizing isn't quite so important. https://www.ravelry.com/patterns/search#craft=crochet&hooks=5.0mm&sort=best&view=captioned_thumbs