How to construct the phylogenetic tree of the whole genus?

[TANGLi83]

Hi guys, I am confused about how to construct the phylogenetic tree of the streptomyces genus. The taxonomy of the streptomyces genus is mostly based on the MLST method, but now I need to use the gene data from NCBI to construct the phylogenetic tree of the streptomyces genus. Should I use the whole gene of the MLST's housekeeping gene to construct the tree? Or I should just use the loci to build the tree? Or the other method? I am a junior in university, have little knowledge of the filed., but my tutor asked me to do that. plus: Sorry for my awkward expression~