LocationRequest locationRequest = 
 new LocationRequest.Builder(
  LocationRequest.PRIORITY_HIGH_ACCURACY,
  10000
 ).build();

locationRequest.setFastestInterval(5000);

I haven't used location services in a long, long time, so I'm just looking at the documentation for 'LocationRequest.Builder` and guessing at your equivalent code because it looks self-explanatory. Builders are a common pattern, used more often in Java-based APIs like this one than they are used in pure-Kotlin APIs. You can look up "java builder pattern" to read about it.

private fun NewLocation() { 
    val locationRequest = LocationRequest.Builder()
        .setPriority(Priority.PRIORITY_HIGH_ACCURACY)
        .setIntervalMillis(0L)
        .setMinUpdateIntervalMillis(0L)
        .setMaxUpdates(1)
        .build()
    mfusedlocation = LocationServices.getFusedLocationProviderClient(this)
    mfusedlocation.requestLocationUpdates(locationRequest, locationCallback, Looper.myLooper())
}

FYI since you're working on a portfolio:

• Function names in Kotlin start with a verb and lower-case letter by convention. Or if it returns a modified copy of an object, you can use a past participle instead of a phrase starting with a verb. For example, I would rename NewLocation() to something like beginLocationRequest().

• The mSomething pattern of naming variables (putting abbreviations in front of variable names) is called Hungarian notation. m stands for "member", but Kotlin properties are not even called member variables. I've never seen Hungarian notation used in Kotlin before, and it is rarely used in Java. It is widely regarded as making code less readable, especially with modern IDEs. I would advise against using it in a portfolio project as it is more likely to damage the impression you want to give than it is to help, especially if you are using it inconsistently.

You are implementing LocationListener in your activity MainActivity. The call for concurrent location updates will therefor be like this:

mLocationClient.requestLocationUpdates(mLocationRequest, this);

Be sure that the LocationListener you're implementing is from the google api, that is import this:

import com.google.android.gms.location.LocationListener;

and not this:

import android.location.LocationListener;

and it should work just fine.

It's also important that the LocationClient really is connected before you do this. I suggest you don't call it in the onCreate or onStart methods, but in onResume. It is all explained quite well in the tutorial for Google Location Api: https://developer.android.com/training/location/index.html