Check if domain names are available with ASP/VB.net

I need a program in ASP/VB.net (Visual Studio 2017) that will do the following: 1. take website URL as a parameter on the webform and go through all pages (have a counter of pages scanned on the form) and find links pointing to other websites. (exclude any links around image: <a><img></a>) 2. take only domain name (example: for http:\\[login to view URL]\us\ it is [login to view URL]) and save it into xml or excel file only once 3. have a field on the webform to exclude certain top-level domains (TLDs), coma separated : ch, ca, eu 4. check each domain it found if it is available to buy - there is a public API for that 5. have a button that just goes through the list of saved domains and does availability check indefinitely in a loop. have a box for number of minutes to wait between each list scan. also a button to stop a scan at any time 6. display a list of available domains as well as email them to email from the webform field