Crafting skill question

What causes your crafting skill to advance? I’m not talking about using better materials, I’m talking about YOUR personal skill level.
all of my engineers make level 3 bolts no matter what level material is used because their personal skill on crafting bolts is so high they make the good stuff all the time.
but my alchemist doesn’t seem to learn a damn thing crafting stuff. his skill is stuck in the lowest of levels. How do I level up my personal skill level as an alchemist like the engineers did with bolts?

if i remember its the skill lvl of engineering x by how many points you put the right points in

edit found it Your base Crafting Skill is determined by your profession skill, but can be modified by many factors, like the quality of used reagents, Finishing Reagents, profession gear with skill bonuses, consumable bonuses, and your profession specialization. This does seem a bit complicated at a first glance, but the new crafting UI in Dragonflight shows clearly what Quality you’re expected to craft the item at in the Crafting Details menu.

https://www.wowhead.com/guide/professions/overview-dragonflight#:~:text=When%20crafting%20an%20item%20in,on%20the%20effects%20and%20quality.

Your skill level (1-100) gives +1 skill. Whatever you make (i.e. bolts) has skill ups in 1 or more trees. For bolts, the Optimized Efficiency and Pieces Parts trees has skill ups.

You also get skills with your Engineering Accessories (+6 each).

So you start with your base skill.

Your crafting gear increases it a little (green tool and blue versions of all slots of gear all have bonuses).

Almost every bubble in the spec tree will add some crafting skill equal to the points invested under some conditions as well as boosts at certain spoke-checkpoints. Every skill has at least one spec bubble that gives flat bonus skill across the whole profession (engineering has a couple I believe?). Other bubbles will only apply to some recipes, not all.

Figuring out exactly which bubbles apply to a particular recipe can sometimes be an adventure but it’s all there.

Even fully skilled, equipped and speced, you can’t reach a guaranteed max-star result on some recipes. Bolts for engineering, however, is one where you can get there fairly easily.