draw/lose in endgame preventing?

You have just started. I looked at one game.
In the above position, you were in check. You had four reasonable moves to stop the check.
- You can move either knight or your bishop to d7
- You could move the knight on b8 to c6
- You can push your pawn to C6.
Instead of any of those, you moved your queen to d7, where it could be taken.
Your opponent didn't take it, instead taking your pawn on c7.
That gave you another chance to interpose a knight on C6, which would have kept you from losing your queen.
Instead, you took the bishop on b5, which protected your queen, but left you vulnerable to mate in 1.
It seems to me that you are still learning the basics of seeing what your opponent is attacking and how to protect your pieces.
I would recommend you take the series of lessons for players new to chess. I am pretty sure they are free for all members.
https://www.chess.com/lessons/playing-the-game
https://www.chess.com/learn-how-to-play-chess
so i shouldn't worry about the 450 drop in points the first day playing?

so i shouldn't worry about the 450 drop in points the first day playing?
No, your 800 starting point was arbitrary. After you start, your rating adjusts very quickly to reach an appropriate level.

Hi! My name is Lauren Goodkind and I’m a respected chess coach and chess YouTuber based in California:
https://www.youtube.com/channel/UCP5SPSG_sWSYPjqJYMNwL_Q
I have tips and resources to help you improve your chess skills so you can win more games.
-I made a video on how to avoid stalemate: https://www.youtube.com/watch?v=WZiZPW0pbZc&t=1s
-If you are serious about chess, I highly recommend you hiring a chess coach to help you.
-Also consider all checks and captures on your side and also your opponent’s side. Always as, “If I move here, where is my opponent going to move?” Do this for every single move.
I hope that this helps.