Another option would be the ESP8266 clone boards, which should be fine for your purposes, alternatively the ESP32, is an upgraded board. They cost ~ 2 euro delivered from either ebay, aliexpress etc. They can be programmed using the Arduino IDE if you're already familiar with that, or via the other usual routes. Built in Wifi and so on, despite the relativity low specs you can do a lot with them. This tutorial give a short primer on the board and a working example of using it to read the values of 2 types of sensor, and display them on demand in a browser via a web server running on the board. Indeed there are lots of options open to you. Once you've had time to process them all please let me know which way you intend to go, or if you have further questions.