Genetics test as of now ,is not a very accurate way to design nutrition plans(it’s still in a very novice stage).
Regarding blood test,you need to check with your doctor(a good basic overall health check up will give a fair idea about your health).
If you experience some specific symptoms,then speak to your doctor/nutritionist about that too…he/she can suggest additional tests regarding that(like low energy could link to low iron levels or memory problems/nerve problems could link to b12 deficiencies).
Hope that helps