You have a projection problem. The shapefile has a coordinate reference system (CRS) that is used as the units of measure in the geometry, and defined in the files PRJ. These need to match.
I suspect that you have added your data to QGIS. Then you went into properties-source and changed the CRS to WGS84. Below is a screen shot of some data using EPSG ...
I am not sure if this is the issue, but when exporting to KML make sure to write the field name that represent the labels in the NameField as you can see below.
Here is the result
If you write another field name, it will be loaded automatically into GoogleEarth
Here is the result
You can create separate polygons in KML format directly when using the Convert format tool without using other tools as follows and using an example:
This is a grid shapefile with 20 polygons
Use Convert format tool from Processing toolbox -> GDAL -> Vector Conversion -> Convert format
Select Input Polygon shapefile (20 polygons above in this ...
Yes, you can use the first 12 digits of that "blockcode" field. The last four digits is called the "block code" and the first digit of those last 4 is the "block group number"
How to split a vector layer and convert it to KML format
The split vector layer tool creates geopackage files by default. If this is a process you do frequently, it may be worthwhile to follow the steps here to change the output setting for this tool. Otherwise, it takes two steps to split your layer and convert it to KML.
Split the layer using the split ...
As per the comment, you need to choose the format you want to convert to by choosing the Save to file option in the 'Converted section, and then picking the format you want to convert to.
You need to end up with a GDAL command that begins with
ogr2ogr -f "LIBKML"
You have to do this because the default option for this tool as per the documentation is ...
Best way to try is via Google Earth. Before you do that:
1. Save your excel file as .csv
2. In Google Earth go to: File -> Import -> select your .csv file from the directory -> click "Next" (but without loosing your mind - specify some properties, depends what you have) until you go threough all options, then click finish.
3. Wait for batch geocoding in ...