Hi need advice what Arduino to buy.

Hi, I would love some help to point out what I need to buy to start my projects.

Questions 1:

The Aurdino must be connected to my wirelss G network and security WPA2. (And external server will control and grab numbers from the aurdino.)

The aurdino will measure Temeratures and send out ultrasound. Must be able to handle temperatures from -25 to + 30

Should I buy Aurdino Uno and then add a “shild” or is there a one piece solution?

What Aurdino should I buy?

Question 2: Another project will need Ethernet access over TCP.

Same goes here. Do I need Aurdino UNO and then add shild to it or can I buy an Aurdino with everything onboard?

What Aurdino should I buy?

Should I buy Aurdino Uno and then add a “shild” or is there a one piece solution?

There are no Arduinos with built-in wifi capabilities. You'll need a wifi shield.

Do I need Aurdino UNO and then add shild to it or can I buy an Aurdino with everything onboard?

There are Arduino with ethernet boards available. But, the UNO and separate shield provides flexibility.

Hi and thanks for the answers.

What wifi shild should I get that can handle G and WPA2 ?