Hi there! Without spending ads, the best way to get organic traffic to your website would be in three ways:
-Targeting places where your customers hang out online (Facebook groups, website forums, etc.)
-Content Marketing – putting out blog posts, thought leadership to build up your brand’s reputation
-Influencers/Partners – finding people relevant to your topic and working with them to reach your potential customers.
A LOT of this depends on your specific product/service and your specific target audience.
Happy to chat through in more detail in case I can help. My e-mail is firstname.lastname@example.org. Thanks!