Start by creating a new widget blueprint, I will call mine BP_HealthBar then open it and copy the videos below to add a progress bar to the widget and set it to change with the players health, if you want to customize further its look you will need to find videos on widgets.
Next go to the BP_InventoryHUD and copy the video below to add the new health bar to the widget. Again if you want to customize the look of your bars then you will need to look up videos on widgets and how they work.
You are now finished, the new health bar will reduce and increase with the players health.
Repeat the same process for each of the thirst, hunger and stamina stats but change the Current Health and Max Health variables for the Current and Max thirst, hunger and stamina variables in the GetPercent_0 function.
Note you wont need convert to float nodes for the other stats, these nodes are highlighted in the image below.