Can you add a whole number to a number with a variable

No, u cant. Because they are not like terms

Examples :
1 + 2vcannot add or subtract because they are not like terms
2v + 4v = 6v...u can if they have exactly the same variable
3x^2 + 2x...cant
x^2 + 4x^2...can...= 5x^2
3 + 3 can
2 + 5x...cant

now u can multiply and divide one...u just cant add or subtract them

Is subtracting.

Also 601 subtracted by 399 is 202.

This is really the only explanation that anyone can really even give here. If this is not what you were looking for then I recommend that you make the question again and more clearly state what you want us to figure out.

-Ɽ3₮Ɽ0 Ⱬ3Ɽ0