Wix provides the hosting.
To connect a domain name to Wix from an external site you have to pay for an upgraded plan.
1) Simple solution (not cost effective)
- Cancel 1&1 hosting
- Pay for an upgraded Wix plan
- Transfer domain name to Wix
This way everything is with Wix and it's less to worry about. And you keep the drag and drop features that Wix provides. The con is that it is very expensive in comparison to other methods. if you simply top using Wix you lose your website and potentially the domain name.
2) Medium complexity (much cheaper)
- Drop Wix
- Keep 1&1 hosting
- Keep the domain name on namecheap. You simply point the DNS to 1&1
- Install WordPress on 1&1 hosting. You should have 1 click install on your cpanel.
This way you have more control on ownership of everything. It's much cheaper this way. Cons would be you don't get drag and drop but honestly you don't need it, WordPress has tons of templates to use that are very good.
If you need more in depth help let me know I'd be glad to help.
Also if you hire it out or get someone to help don't ever put it on someone else's hosting or let them buy the domain name. What happens if they disappear one day, stop paying, or worse try and get you to pay to give back your own content.