You can import .dll's when your program requires something by using the keyword 'Import'. Let's say you're making an Email sending program, you would have a line of code at the top of your source reading:
'Imports System.Net.Mail'
(For those of you who know c#, it's the same as the keywork 'using')
Picture example:
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Declaring variables and constants is easy to do in Visual Basic, you will either use the keyword 'Dim' (variable) or 'Const' (constant) then the name of your variable/constant, and what it is (a string, integer, etc.). For example:
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Beware when declaring variables/constants, if they're declared inside a block of code then they will be exclusive to that code (unless you use byref or byval, but that's further than this tutorial currently goes...), but if you make them outside a block of code then they're global variables/constants and can be used everywhere.

Let's say you want a message box to display one thing if a number = 10, another thing if said number = 11, or a totally different thing if it doesn't equal either 10 or 11
You would use a code that looks like this:
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Let's say you want a block of code to keep doing something, then you would add a line with the keyword 'Do' before said block, and a line with the keyword 'Loop' after said block. Like so:
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Try statements are very useful, if a code, for whatever reason, may provide errors then a try statement will make sure that these errors are avoided so that your program doesn't crash, then activates an alternative block of code. Basically, it works like this:
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