I make HBA1C test b4 4month and I get 7.4 after that I stop smokig and I made diet and sport and I test but the result is 8 is that mean its Diabetes?

Diabetes. That is not typically the way I diagnose diabetes, but is diagnostic. your blood sugar is going to meet the diagnostic criteria. You should see a doctor right away. Who is ordering your Hgb A1C tests? It seems to me they should be reviewing the results with you and advising you on what to do now.
Hyperglycemic. These values are diagnostic of diabetes mellitus and I recommend that you consult a physician for proper treatment and followup. Diet is key in bringing down your HgbA1c.
Yes. Technically, a hemoglobin A1c reading is diagnostic of diabetes if it is equal or greater than 6.5. So, yes, you do have diabetes, despite the dietary and lifestyle changes you have made. While these are good things, you will likely need medication to regulate your blood sugar in addition to low carbohydrate diet and increased exercise. Talk to your doctor soon about your options. .