The people Israel always understood that there were heavens (plural). It's why they are called "shamayim" (שָּׁמַ֖יִם).
"Hell" is often the result of a mistranslation in the B'rit Chadashah. Gehinnom is the place where souls are destroyed forever and with finality. And yet certain "scholars" decided to use the same word "hell" (ᾍδης), to (in error) describe both the place where the dust of man goes, waiting for resurrection, and Gehinnom. Messiah Yeshua was quite careful in noting the differences.
"Hell" is analogous to the Hebrew word "She`ol" (שְׁאול). When שְׁאול is found in Tanakh, it is translated in the Septuagint as ᾅδης, pretty consistently. Where the concept of She`ol is expounded on significantly is in the book of Iyov (Job), which is, overall, a very informative book about life, death, free will, forgiveness, repentance, and the sovereignty of HaShem.