Start with the angle the knife came with and hold it steady: Buck's how-to says that, ideally, you follow the edge angle the blade had when new. The makers' own numbers differ: Buck's how-to page says Buck tends to grind to 13-16 degrees per side, while Kershaw's FAQ says its knives are generally sharpened to between 20° and 22° without saying per side or total.
A beginner's biggest problem is not the angle they choose but the angle they fail to hold. Buck, Kershaw and Case each tell the reader to keep one angle, in their own words: Buck's how-to page to follow, ideally, the angle the blade had when new; Kershaw's FAQ to maintain a consistent angle; and Case's knowledge base to keep the same angle through the entire stroke.
Each maker's own figure, and whether it says per side, is set out in what angle knife makers sharpen at.
Buck's 2021 Journal post finds its angle by holding the blade perpendicular to the stone, rotating it halfway between vertical and horizontal, around 45 degrees, then cutting that space in half for a 22.5 degree angle, which the post says works well. Buck's how-to page gives a rule of thumb instead: hold the blade so its back is about one blade width up from flat on the stone.
To check, the how-to page prints a felt-pen test: shade the bevel with a black felt pen, take two strokes on the stone and examine the edge. If you held the proper angle, all the black is gone; black left on the top of the edge means the back of the knife is too far from the stone, and black on the bottom with the top clean means the knife is too flat.
Buck's how-to page says the angle on a Buck knife is set by how Buck feels it will be used: heavy use needs a strong and blunt V, while skinning or filleting would need a deeper but more vulnerable V. A micro-bevel two or three degrees steeper gives you most of the durability back.
Chopping tools want steeper, around 25 to 30 per side. Soft steel at an acute angle simply rolls.