Why E5

Hello!  I am pretty much a beginner when it comes to tactics.  This is a Fritz 19 Easy Game with a practice book of All Possible Scandinavian Defense Moves.  I am wondering why Fritz recommends E5.  I was going to go for E6 to support my D5 pawn.  Is it because it allows me to occupy the center?  Or is it, as Fritz tells me to "block a pawn?"   If White pushed the pawn, that could be easily dealt with, no?  Why is it necessary to block the pawn?  I know this is a very simplistic question for all you chess experts out there, but for me it is knowledge I need so I can improve my game.  I will appreciate any responses.  Thank you!

Thank you for taking the time to explain that to me. I like to know the reasons behind each move and it's hard to understand what's going on until you think in the way you just described to me. Thanks so much!

Also, in regards to the usefulness of "blocking the e-pawn."

Imagine if white were able to get their pawn onto e5 and protect it (with f4, Nf3, or a B move followed by d4). That pawn on e5 would be an annoyance limiting how you can develop. For example, you wouldn't be able to safely or quickly play Nf6 - a natural place to put your knight which makes it a useful defender of the kingside. This could cause problems down the line if your opponent tries to create an attack against you on that side of the board.

All questions are welcome when it comes to chess improvement*. e5 is recommended simply to take more space in the center of the board (e4, e5, d4, d5). These four squares are the most important squares on the board, so control over them is vital in order to fight for an advantage*. You also asked whether your opponent pushing the pawn is a problem, which it definitely is. His pawn, if on e5, would control or occupy 2 squares (e5, d4) and fight for a 3rd square (e4), leaving you with only one central square under your control. The pawn on e5 would also effectively prevent you from developing easily, and could be supported with the d and f pawns to control the center almost completely.

dxe4 is also an option, since it forces the white bishop to move twice in the opening, but it is usually advisable to avoid breaking the tension until you are best prepared to exploit the resulting explosion.

Also, e5 here frees your dark squared bishop, allowing it to develop more freely, while also keeping options open for your light squared bishop. It also makes development of the kingside knight easier due to the absence of the possibility of the e4-e5 pawn push.

beacuz if takes takes takes check takes there takes takes there there there there check check block there takes captures then after 99 moves it is mate

Most importantly, I wouldn't trust anything Fritz 19 says. Engines are very far away from understanding chess, and even further away from teaching chess. Anything the machine says may be OK or may be nonsense, and you won't have any idea which is which.