My understanding from your question is that you would like to programmatically (using LabVIEW) send input to and click a button on an existing HTML website, is that right?
If yes, then you can use ActiveX calls to embed a web browser into the front panel of your VI and then use its invoke node to input a text to a form or click a button. Another way is to use the lower-level TCP VIs in LabVIEW, but you need to understand HTTP protocols to successfully use this. See below examples to get started.
ActiveX
https://decibel.ni.com/content/docs/DOC-25396
https://decibel.ni.com/content/docs/DOC-12454
TCP VIs (HTTP)
https://decibel.ni.com/content/docs/DOC-2230
http://zone.ni.com/devzone/cda/epd/p/id/3153
FYI, LabVIEW Internet Toolkit has been deprecated starting LabVIEW 2012, so it is not recommended to build a new application using that.
Hope this helps.
Regards,
A. Yodha
Applications Engineer | National Instruments
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