Yes, the Slavic "хлеб", etc., appear to be cognates with the Germanic "loaf", etc. Wiktionary [0] says they both come from Proto-Germanic "hlaibaz" (reconstructed [1]).

[0] https://en.wiktionary.org/wiki/loaf#Etymology_1

[1] https://en.wiktionary.org/wiki/Wiktionary:Reconstructed_term...