Remove your mods; they're breaking things because they're not compatible with the new version. If you absolutely must run modded, then you're going to need to either downgrade to the previous version of Valheim, or wait for the mod authors to update their mods to work with the new memory maps.

To run the previous version of the game:
In the games list: right-click Valheim, choose "Properties".
Select "Betas" in the menu on the left.
Select "default_old" in the drop-down on the top-right.