What you're asking for is called "left aligning normalization". It represents variants in the most parsimonious notation and is one of the best practices I've encountered and continue to use all the time.
If you have the VCF file this data comes from and the reference sequence used in the analysis, you can use either
bcftools norm (bcftools) or
vt decompose | vt norm (vt) to get to where you need from the VCF file. I'd recommend the latter as it makes tracking changes easier by adding
OLD_VARIANT INFO fields.
If not, it becomes a much more challenging task because you're going to need to compare the REFERENCE sequence and ALT alleles manually to get to your solution.