Age 16, t cholesterol 370mgh/dl , hdl 1.16, ldl 7.36, t chol/ hdl ratio 7.91, sugar level normal.. is this very high

Yes. Way, way high: Cholesterol is not the sum total of cardiac risk, but you need to under the care of a competent physician.

Something isn't: adding up. Perhaps typo...your ID info says age 76, not 16. Total cholesterol is given in mg/dl (370 IS high), but other values in mmol/l. However LDL of 7.36 mmol/l (284 mg/dl) is QUITE high, too. Unfortunately your 1.16 mmol/l (44 mg/dl) HDL isn't very far into the protective range. Ratio is high. Notes say you have had heart stent so cholesterol needs to be much lower;need meds. Review with Doc