It won't let me enter Ultimate Team from the start of the game.

Please help me

Hey jalesdaniel7 Please open the Ultimate Team web app go to your squad, delete the current squad, and create a new one. make sure to use different players, formations, and tactics.  
From the FC 25 Main Menu, go to Settings> Profile> Delete and remove the file UT Squads Update. Go back to Ultimate Team and start a new game. 

Hey community manager if I do that will my orignal players be deleted

No, you are not deleting your players, just your squad, which you can always recreate. Those player items will remain on your account.