The João Gilberto guitar pattern — the sound that defined bossa nova. The thumb plays the bass on beats 1 and 3 (root, then fifth, or the next chord's root), and the fingers pluck the upper three or four strings in the bossa clave rhythm: 1, and-of-2, 4 | 2, and-of-3. Everything is fingerstyle; the "strum" marks are plucks, not strums.
How it sits on the clave: the fingers are the clave; the thumb is the surdo. That is why one guitar can carry a whole bossa. Gilberto varied the finger rhythm constantly (anticipating the and-of-4, doubling the and-of-1); this is the plain two-bar form every variation returns to.
Listen for the thumb never moving and the fingers never landing on 3. The piano here only answers with short rootless chords on the clave strokes so the guitar stays in front; mute it to hear the guitar alone.
Practice: thumb alone for a minute; then add only the chord on the and-of-2; then the rest. Voicings are standard shapes (Fmaj7 1x221x, Gm7 3x333x, C7 x3231x). No transcribed source — authored from standard practice.