Before you change anything
Get the correct nameservers or IP address from your hosting provider and identify where your domain's DNS is currently managed. Save the old zone records first, especially if business email already works. If possible, have a recent backup of the website.
Option A: change nameservers
Nameservers decide which DNS service answers for your domain. If your hosting provider asks you to use its nameservers, sign in to your domain registrar and replace the old nameservers with the exact ones provided for your account.
Our nameservers include ns1.estha.net, ns2.estha.net, ns3.estha.net and ns4.estha.net. Check your welcome email to see which nameservers apply to your account.
Changing nameservers may move management of more than your website. Recreate necessary MX, TXT and other records on the new DNS provider before switching when possible.
Option B: keep the nameservers and edit DNS records
If you manage DNS through a registrar or external service, you can often point an A record at your hosting server's IPv4 address and configure www using a CNAME or the records recommended by your provider. Do not use IP addresses copied from another customer's tutorial.
What about email?
Email delivery may rely on MX, SPF, DKIM and DMARC records. Changing nameservers without copying those records can disrupt email. Test both send and receive after making the change.
How to check it worked
DNS caching means some visitors may see the previous destination temporarily. Once updated, load the domain in a browser, test the www version, verify HTTPS and confirm contact forms or store functions. If problems remain, compare the current public DNS response with the intended values.