Have a look at the thread here:
Round a sensor number on a card - Configuration / Frontend - Home Assistant Community (home-assistant.io)
Created a template sensor and use the template
{{ sensor.keg_temperature | round() }}
By changing the value in the brackets for the round function, you can determine how many decimal places you want. The example above rounds to the nearest whole number.
Unfortunately without custom cards or one of the options by eggman in the linked thread, you will have to create a wrapper template sensor for every sensor you have.
If you are happy to use custom cards, try the mini-graph-card, disable the graph to show only the value and set decimals: 0 per the documentation.