You can check keyword research tools like Google keyword planner, Long tail pro, wordstream, Buzzsumo etc to find the most searchable keywords and from that decide primary keywords according to your business niche. You can try Google trends for topics. Google trends will show you latest trending articles and topics people are searching for. You can check news sites according to your business niche. For example if your business is related to ecommerce you can check the topic leading ecommerce update sites like entrepreneur, wjs, retail business news sites etc.