How should we write a business plan for a startup if we have dozens of products and services in mind?

It will require more due diligence but don’t skip it. You will also need to decide how you will market all these products and what will the cost be to produce and what will the margins be? When you see your margins you may also eliminate some products. Who will your biggest competitors be and what are they selling these products for? That will also dictate your pricing. I could go on and on but hopefully, at this point you see the need for a business plan. You can get a great business plan template at www.worldsgretestbusnessplan.com/freebook