what do play against 1.e4 d5

There was one option that was showed to me instead of taking the d5 pawn in the Scandinavian. The guy who showed it to me said it was Alekhine's reply to it or something. I think it likely is a transposition of Alekhine's Defense

I don't know how well it works but it's an idea to try out nonetheless.

This is what usually happens in your sequence

Usually I play:

Not 8...Qxd5?

If black tries to hang on to the pawn there are quite a few traps. Good for blitz

1.e4 d5 2.exd5 Qxd5 3.Nc3 Qa5 4.d4 Nc6 5.Nf3 Nf6

Per your line--Black must play 3. Nf3  Bg4 when you may get play something like this:

Have you tried this?

StupidGM Come on, at your rating you must recognize Qe5+ is a  mistake, even a beginner's mistake?

This gambit yields about an equal game for both sides. If you like to attack and are good in tactics then play the White side. If you like to defend then play the Black side.

Possibly helpful:
A Simple Chess Opening Repertoire for White by Sam Collins
http://www.jeremysilman.com/shop/pc/A-Simple-Chess-Opening-Repertoire-for-White-76p3916.htm
http://www.gambitbooks.com/pdfs/A_Simple_Chess_Opening_Repertoire_for_White.pdf
My First Chess Opening Repertoire for White by Vincent Moret
https://www.newinchess.com/Shop/Images/Pdfs/9033.pdf
Playing 1.e4 - Caro-Kann, 1...e5 and Minor Lines by John Shaw
http://www.qualitychess.co.uk/ebooks/Playing1e4CaroKannandothers-excerpt.pdf
Beating Unusual Chess Defences: 1 e4 by Andrew Greet
https://www.newinchess.com/Shop/Images/Pdfs/8665.pdf

The main thing for White is to try to gain tempos on Black while keeping your pieces protected and not jamming future development.  It's hard to end up at a disadvantage that way.

I just saw this on youtube

This is one of my ways to win as White against Scandinavian defense:

oh sorry I didn't see this post until now haha!