Welcome to alternative health :))) there are many functional doctors, and others who perform this kind of stuff.

For example Organic Acids in Urine Test gives you some 70-80 metabolic markers, which some folks interpret. There's no large scale RCTs or studies on this, so it's a bit dubious. But I did one and the practitioner correctly read the leaves to suggest some things that were missing and which helped me (glutathione and B1).