How to Pick Single Notes on an Acoustic Guitar
Picking individual notes (not strumming across all the strings) on an acoustic guitar works on the same alternate picking principles as electric (see [[alternate-picking-basics:the article on alternate picking]]), but the acoustic's thicker, stiffer strings need a few adjustments.
Thicker strings need a different force balance
Acoustic guitar strings are thicker and under more tension than electric ones - too light a pick strike simply won't make them sound at full volume. At the same time, too much force gives a harsh, scratchy edge rather than a louder clean tone - the force balance is worth re-finding on its own, separate from habits built on electric guitar.
Pick angle matters more on acoustic
A small angle of attack for the pick (see the article on pick grip), which is more of an option on electric, becomes nearly mandatory on acoustic - a thick string met dead perpendicular by the pick needs noticeably more force and gets stuck more often.
Body resonance changes how the attack feels
An acoustic's hollow body resonates differently than a solid-body electric run through an amp - the sound of a pick strike feels more immediate and responsive right under the hand, with no delay from signal passing through electronics. That changes how your own timing feels, and takes a bit of getting used to when switching between instruments.
Single notes against ringing bass strings
Playing a lead line on acoustic often sits next to bass strings still ringing from momentum - extra resonance from neighboring strings is more noticeable on acoustic than on a clean electric tone. Muting unused strings with the picking-hand palm (the same principle as in muted strumming) is especially useful here.
Where to start training specifically on acoustic
Take a simple scale or short riff that already feels solid on electric (if you have that experience) and play it on acoustic at a comfortable, slow tempo - the difference in force and angle becomes obvious right away, and it's easiest to calibrate on material you already know, rather than on something new at the same time as a new instrument.
Try it in practice
Open the metronome