(Set Ignore Move Input) node to true and (Set Ignore Look Input) node to be true and attach the target to player controller. To enable all movement again do same but leave bool unchecked for false.
Here try this. Make 2 Functions in character BP, call one enable mouse and other disable mouse (or what ever you want to call them) then set up like these images show.
This is set up in character event graph to call your inventory.
Then in in the (Enable Mouse) Function we set this up.
Finally we set the (Disable Mouse) Function up like this.
This should get you running right and then you can just call these functions when pausing the game, going into different menus, etc.
Hope this helps.
P.S. Also the crosshairs is just my set up because I have crosshairs lol so you can ignore that.
Also in character BP on Event Graph, Call (Event Begin Play) node and create widget there like this.
