So I'm building sharepoint pages that are consisted of web parts. I need to send parameter to a page, and that send it further to these web parts, and I have no idea how to do this...
OOTB way:
You can use query string filter web part to capture the query string values and pass it to the web parts.
Custom WebParts:
You can use the following code snippet to capture the query string.
Request.QueryString["param"]