捕 is mostly used in compounds: 捕鱼 (fish), 捕猎 (hunt), 逮捕 (arrest), 捕捉 (capture/catch). The figurative 捕捉 can mean capturing moments, details, or opportunities. 捕风捉影 = to chase shadows (making accusations without evidence).
Left hand-radical 扌 (side form of 手) — the indexing radical. Anchors 捕 in the family of hand-action verbs: 抓 (grab), 拿 (take), 扑 (pounce). The hand is what does the catching.
Right 甫 supplies the sound (fǔ → bǔ, a regular labial alternation in the same phonetic family). Same phonetic appears in 哺 bǔ (feed), 浦 pǔ (riverbank), 铺 pū (spread). Semantically silent — pure sound carrier.