How can the multiple selected checkboxlist's items be sent to database tables?

I'm very new to programming... and , I need to make a Form. When a user click the submit button, the value inputed in textboxes and selected checkboxes will be submited to sql tables (Asset and Installation). 

There are 3 tables:

                 Asset(AssetID[pk], Model, etc..)

                 Software (SoftwareID[pk], SoftwareName)

                 Installation (InstallNo[pk], AssetID, SoftwareID, SoftwareName)

It's a many to many relationship, so I create an extra table (Installation).

 

The form is like the following:

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