How to upload split application binary at Play Store

My game APK file size increased by 100mb so I require to split it. So now I have two files with .apk and .obb extension. But at play store there is no way exist to upload OBB file.

Here is my play store account screenshot:

I have uploaded APK file but where to upload OBB file??

This is explained in the Google Play Store documentation: Add or test APK expansion files - Play Console Help

Go to your Play Console.

Select your app.

On the left menu, click Release management > App releases.

Next to the release type you want to update, select Manage.

Drop or select your app’s APK file.

You’ll see a list of APKs that are associated with your release. Next to the relevant version code, select the add icon .

Choose whether you want to upload a new file or attach an existing expansion file.

If the APK hasn’t been published yet, you can change or remove an expansion file by selecting another file or No expansion file. You can’t remove expansion files from an existing release.
Select Save.

Once you upload the apk there will be a “plus” icon to add the expansion.