Before taking any drugs you should do more tests. The only fact of having hbsAg positive does not men you should take the most expenive drugs available for hbv treatment.
You should do:
Liver ultrasound, fibroscan.
Blood test or Alt, hbsag quantity in ui/ml, hbeag, hbv dna quantity. Hbcag iggM.
If you are chronic you may need taking those drugs for life and Lamivudin may inot be the best option.
lamivudine is NOT an hbv drug anymore since years it makes virus mutations which worsen the infection.
look for a liver specialist that doctor doesn t know hbv and doesn t know hbv drugs, antivirals have no effect on hbv virus and are used only to stop liver damage so you have to take them from decades to all life
tenofovir is the only 100% safe drug for hbv since there are no known mutations or resistance to it and of course it is the most potent on hbv, it may take about 17years to clear hbv definitively