Welcome to the forum and thanks for asking our advice.
Congratulations on your new gun. Is it your first firearm?
I generally field-strip and inspect every gun I ever get before shooting. In recent years, I have read the advice of others suggesting that a full cleaning is in order because some factories have been know to leave metal shavings and debris inside. It is a sad comment on quality control.
If it is a gun with which I am unfamiliar, I usually ask the owner (if used) or store clerk (if new or used) to show me how to strip and reassemble.
I have used a variety of oils over the years. Any good machine oil seems to do as well as any other. There are some specialty lubricants in my cleaning box, mostly from www.tetraproducts.com/
But even motor oil will do in a pinch.
Some guns are intended to run "dry", with just a little lubrication. Some do better with more. I don't know about the Beretta. See what the owner's manual says and ask the seller. Follow the owner's manual precisely. Even the most expensive gun oil is a lot cheaper than what you will pay a gunsmith to fix excessive wear.