Am I dreaming or is this really possible?

[gary.cantigneaux]

1) archive and display on a Web page temperature and humidity data from some sort of sensors, if yes which One?

Don't know what you mean with "archive", but you can connect different sensors to your Raspberry Pi, configure OpenPlotter to receive the data and then have it displayed on a web page.

As for which sensors people in this forum can help you out, but you get far more easily help by just googling for "raspberry pi temperature sensor tutorial" etc - plenty of tutorials out there. Ditto for humidity.

2) import and send nmea1083 and 2000 to an ipad for Inavx?

You can connect  nmea0183 data sources to OP and the data will be available over TCP for iNavX.
Also NMEA2000 sources can be connected with the appropriate adapters to OP. OP can convert most NMEA2000 data to Signal K format and Signal K data can be converted to NMEA0183 format, available for iNavX like data that was originally in NMEA0183 format.

It looks like iNavX support NMEA2000 data in Chetco's propietary format, but OP currently does not send that afaik.

3) send aïs data with the moitessier hat?

Moitessier hat seems to be receive only.

4) I presume that I will need some sort of double wifi antenna if I want to emit to a remote server but also send data to devices onboard such as an ipad?

What do you mean by "remote server" here? I
f you want to make your onboard data available remotely (like from home when the boat is in the marina or a friend can see your data when you are sailing) you need Internet connectivity with wifi or 4g. There are multiple ways to do it and the exact setup depends - for example my own boat has a local wifi and remote connection is 4g, so I don't need a second wifi adapter.

Thanks a lot for your help, this really helps.

So for the moment, i have just received my Raspberry Pi3+ (Thanks Santa) and i will install OP tonight or in the coming days. 

However, i did not yet find a good tutorial on how to connect the temperature sensor to OP, i found the way to have the data on the Raspberry but not the steps in need to take in OP. Can you help me with this?

Thanks,

Gary