When creating a new workspace, you can configure a subdomain under the TwicPics domain. You can choose any subdomain you like, pending availability.
Example: https://mycompany.twic.pics
Custom domains
Pro and Enterprise plan users can setup custom domains of their own (using custom CNAME.)
Example: https://assets-subdomain.yourcompany.com
Related: this article on SEO best practices explains why using a custom domain is recommended.