The task of passing data from one Form to another is simple, and there are several well known ways to do it, including the use of Interface as preferred by Sergey, which is an excellent, and proven, technique,mastery of which will have many other benefits to you as a programmer.
OriginalGriff here on CodeProject has a series of three articles that demonstrate other ways to achieve this; this is Part 1, which has links to the other two articles: [
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Your choice of technique might be based on the required sequence of transmission of data (workflow) ... item-at-a-time, or all-at-once ... or, the volume of information to be sent, the data Types involved. If you are transmitting a bunch of text-data, that's one thing; if you wish to pass instances of complex objects (Classes, Structs, etc.) that's another.
However, the task of getting the data you now have access to on Form2 into the URL fields in the currently opened web-page is the more difficult task here.
Is the web-page where you want to insert the data a web-page you have created and have control over ?