How to limit input type = number to only positive numbers
The easiest way to do this is to set the minimum value in html:
<input type="number" min="0">
If 0 is also not allowed, you can set min = "1" or any other number you need.
This will limit the number selector on the right side of the input, but does not add any extra checks in case the user entered a negative number manually!
To avoid this, you can add a small js check:
<input type="number" name="input_name" min="1"