There is a lot one can find about (existing) domains. Perhaps you are doubting to by a domain name from someone else?
Or you want to register a domain name that has just been released?
Do you due diligence and start sleuthing!
Some tools/tips to get you started!
How to check all dns records of domain?
dig stijnbernaer.com ANY +noall +answer dig stijnbernaer.com +short dig stijnbernaer.com
This will give you insights in TXT, MX, A records and other DNS records: DNSKEY, RRSIG, NSEC, … . The nameservers. Note: sometimes this information is not public (e.g. hidden by Cloudflare).
Or use an online tool like
How to see what (website) has been on the domain name over the years?
Go to https://archive.org/web/
Look out for foreign languages. Not that is by definition a problem, but it could an indication it has been abused for spam, black hat seo, … .
Check history of DNS changes?
Lots of changes could mean several owner changes, which could be suspicious (used for spam, bad seo practices) but does not has to be.
How to find current information (technical and ownership) of a domain?
Some companies offer a history of whois information.
Want to find out information about IP?
Download the databases from e.g. maxmind.com and install the geiplocation command.
Next, tou can do Geo Ip Look ups.
Or just use a online tool to do so. E.g. iplocation.net