There are a number of possibilities. For example, download and index the whole genome, and use samtools to extract regions of interest:

samtools faidx genome.fa
samtools faidx genome.fa chr24:40902129-41709809 > region1.fa

If you have bed/gff file of coordinates, then you can use bedtools getfasta and if you have just couple of coordinates to extract the you can try seqkit faidx which is similar to samtools faidx