You need to configure the DNS pointing on your hosting service platform, directing the desired domain to VTEX.
In your hosting platform, fill in the following settings:
Store address: www.site.com.br
Entry (subdomain): www
Type: CNAME
Destination: www.site.com.br.cdn.vtex.com
To redirect the root domain (without www), you need to create 2 records (one CNAME and one A type) on the platform where the domains are hosted:
(In the example below, we use Direcionar)
- A-type record pointing to the Direcionar IP
Type: A
Entry: <blank>
Value: 52.8.174.221
- CNAME-type record so that Direcionar performs the redirect:
redirect.www.site.com.br.direcionar.com.br
Type: CNAME
Entry: redirect
Value: www.site.com.br.direcionar.com.br
The domain without www should point to 52.8.174.221, and must also redirect to the root domain. As shown in this tutorial: Melhores práticas para acessar a loja sem www
Note: If you have any other type of record configured, you’ll need to delete it, keeping only the configuration above 
If you already have a legacy store and want to point it to a new version of your store on VTEX IO, this configuration is handled by VTEX support. Simply open a ticket requesting the DNS pointing to VTEX IO.