Spearfishing is the most hands-on way to fish there is. You freedive down on a single breath and hunt with a speargun or pole spear, which makes it part diving skill, part fieldcraft, part patience. Done well it is also about the most selective and sustainable fishing going, since you choose exactly what you take.
It builds on freediving and snorkelling, so comfort in the water and a decent breath-hold come first. A course teaches the diving, the safety and the hunting technique together, which is far safer and quicker than piecing it together yourself.
The instructors on adventuro run spearfishing courses and guided sessions for the right experience levels. Respect the rules, never dive alone, and you will eat very well.