HLOOKUP is VLOOKUP turned on its side. It searches the top row of a table and returns a value from a row below:
=HLOOKUP(lookup_value, table_array, row_index_num, [range_lookup])
The row number counts from the top of the table you give, starting at 1 for the row it searches. As with VLOOKUP, use FALSE for an exact match and TRUE for bands sorted left to right.
You'll meet HLOOKUP in sheets laid out with months or years across the top. XLOOKUP and INDEX with MATCH also work sideways, and they don't break when a row is inserted, so they're the better choice for new work.