I2C is a bus. You can compare it with a street with houses where each house has an (unique) address.
The protocol says to first send a 7-bit address telling a device "hey, there is data coming for you" or "hey, I want some data from you". Only the device whose address matches with the received address will react (accept data or start sending data).
So as long as each device has a unique address (wifi, AMG8833, ...), there will not be a conflict.
On a 328P processor, the processor pins A4 and A5 also carry the I2C signals. On other processors, the I2C signals are not on the same processor pins (e.g. Mega, Leonardo, Uno Wifi). Hence there was a need to have dedicated board pins on the Arduino; those are marked SCL and SDA.
Note:
Be aware that an Uno WiFi Rev2 is not an Uno; 3rd party libraries that directly access processor registers might not 'work'.
PS
changed Uno WiFi to Uno WiFi rev2 after DrAzzy's comment.