Kia Ora rata5.
Did you read the link to malwarebytes.org that YoKenny posted?
There is a removal procedure there involving the download of a free program (MBAM) which is a very good scanner/remover. Highly recommended.
Go through the steps as recommended. Once the MBAM program has been installed and updated, (choose the free download button to download it) disconnect from the net for the scan and removal. Run a quick scan, a report will appear, select everything it finds, then click "remove selected" (which will quarantine the malware items) and if prompted to restart to complete removal, do so immediately.
Run another quick scan after the restart. Post the first and second scan report. Scan reports can be located in the MBAM GUI by pressing the "logs" tab.
The log can be copy and pasted to your reply, or added as an attachment.
Later we'll talk about how to create some protection to make this sort of thing less likely. Do you happen to remember the website/link you clicked on? (Don't post a working link to it here, please.)
The chances are with this sort of rogue program that you will not be able to successfully remove it using add/remove programs. Do try, though.
Must be a lot of people get sucked into these; it's a multi million dollar scam. Literally. It's big business for organized crime gangs, often based in countries like the former communist block, S America, Asia etc.
If you google "rogue antivirus" there are almost 1.5 million results. It's very common. There are websites devoted to recording/reporting and removing these.