Hi, first of all ESP-8266 WeMos needs 3.3V (the module you rappresented does not have voltage regulator), after this BME280 needs I2C, the I2C for ESP-8266 WeMos is:
|D1|IO, SCL|GPIO5|
|D2|IO, SDA|GPIO4|
The HMC5883L seems to have I2C too.
I suggest you to read Arduino documents regarding I2C, test them separately, download the arduino IDE and use the examples.
Of course you can interface the Arduino IDE with ESP-8266.
There are a lot of tutorial on the web about this CPU and all the alternatives.
Last but not least there are version of ESP-8266 with battery holder and charger integrated.
Tommaso