In Assam, the main portal for government services is Sewa Setu (it used to be called e-District Assam). You can apply for caste certificates, birth registrations, non-creamy layer certificates, and more. If you're not comfortable doing it online, there are Public Facilitation Centres and CSCs across every district. One tip: update your Aadhaar with your current phone number before you start. You'll also want your PAN card and bank passbook close by.