How do I preview a presentation in Zoho Show? Any sample codes?
HTML Sample Code:

Upload Presentation for Preview: <input type="file" name="document" size="38"> <br><br>
<input type="hidden" name="apikey" value="423s*****">
<input type="hidden" name="language" value="en">
<input type="submit" name="submit" value="Preview Presentation">
</form>
Curl Sample Code:

curl --request POST \
--header 'content-type: multipart/form-data; boundary=----WebKitFormBoundary7MA4YWxkTrZu0gW' \
--form document=@/Users/username/Presentation/Sample.pptx \
--form 'apikey=423s*****' \
--form language=en

You can also build and test Preview Presentation requests right from your browser with Office Integrator
Postman Collection.