CA Seller's Permit and Business License

[imwinnnie]

Hello, 

I'm stuck working on my seller's permit at the moment for my dropshipping store with questions relating to things such as nexus, projected monthly sales, and projected monthly taxable sales, etc. 

I was wondering if anyone knows a site/resource or person that specifically helps with these specific questions? I will most likely have more questions if there's more information I have to fill out but as of right now, I'm stuck on that. 

Thank you.