You find a (preferably local, clinical grade so HIPAA/GDPR applies) lab to do a sequence of your DNA. There's some parameters (e.g. coverage rate of your sample) to consider so you might want to look around as prices and services offered will vary.
They'll return a BAM file to you which contains your genome, consider this the raw data. You can take this data to screening services that specialize in analyzing your genome for specific purposes. E.g. here's a service that specifically analysis for the sake of genealogy: https://www.yfull.com/
I've only dipped my toes into the topic but that's my base understanding so far, it's pretty intimidating at times but quite interesting.
They'll return a BAM file to you which contains your genome, consider this the raw data. You can take this data to screening services that specialize in analyzing your genome for specific purposes. E.g. here's a service that specifically analysis for the sake of genealogy: https://www.yfull.com/
I've only dipped my toes into the topic but that's my base understanding so far, it's pretty intimidating at times but quite interesting.