How to Point a Domain to a Website but Keep Email Elsewhere
Domains & DNS · Self-help guide
You can point your website to one service while keeping email with another provider. To do this, change only the website-related DNS records and leave the email records in place. Log in to your DNS provider and open the DNS zone. Update the A record for @ to the website server IP, or update the required CNAME record if your website provider uses one. Do not delete MX records unless you are moving email as well. Also keep SPF, DKIM, and DMARC records that belong to your email provider. After saving, test the website in a browser and send a test email to the domain. If email stops working, check whether MX records were accidentally changed or removed.