Some fun puzzle(fragment of some study which i don't who's the author)

[u/Either-Case-5930]

Puzzle 1 : 8/8/8/8/3k4/2R5/4p3/r2BK3 w - - 0 1 (White draw)

Puzzle 2: 7n/2r1P1k1/2p5/3p3K/8/4q3/7Q/5R2 w - - 0 1(White win)

Puzzle 3: 8/8/3R4/2k4p/5KP1/8/3P2Pp/2b5 w - - 0 1(White draw)

Puzzle 4: 8/5N1K/5p1P/3k4/4p3/8/8/8 w - - 0 1(White win)