According to Wix, connecting a domain purchased outside Wix, is possible only for Premium plan. So if you already have a Premium plan on Wix you can refer to these steps on how to connect your domain.
To point your domain to Wix, you have two options: by using Wix nameservers or using A/CNAME records.
Pointing your domain using the nameservers of Wix
Go to this page and copy the values from the text:
After you copied the values you only need to change nameservers at Hostinger.
Pointing your domain using the A/CNAME records of Wix
Alternatively, you can point your domain to Wix via A/CNAME records.
Open your DNS Zone editor by navigating to Hosting → Manage → DNS Zone Editor:
Choose which domain’s DNS Zone you wish to manage:
Click the edit button near your A record and enter IP address you have copied from Wix:
Do the same for CNAME record by replacing your existing WWW record to point to CNAME record you’ve got from Wix:
After you specify new A/CNAME/Nameserver records, propagation will start which can take up to 24 hours to fully propagate.
That’s it! Now you know two ways of pointing your domain to Wix.