Compare dates

Okay, your spreadsheet is a little wonky. It probably has something with you using =TODAY() in the B column, but since today (as I type this) is Oct 2, and your first row shows a start date of Aug 1, I'll assume that should be an output of 1-3 months, and not < 1 month.

This equation works for the dates you provided in the text above:
=CHOOSE(MATCH(DATEDIF(A2,B2,"m"),{0,1,3,6,12},1),"< 1 month","1-3 months","4-6 months","7-12 months",">1 year")

Just drag it down the C column and you should be good. There is a caveat, in that the third example in your spreadsheet has Nov 2 in column A. DATEDIF expects the start date to be the first variable input, so if it is possible that column A date can occur after the column B date, you will need to check for it and adjust the formula above accordingly (using IF, MAX/MIN, IFERROR, or something along those lines).

Isit possible to ignore column B and add TODAY() to the formula..

Yes, just replace B2 with TODAY()

Isit possible to have the same in VBA MACRO

Yes, but macros are always slower than a comparable formula solution

What should I add to the formula to add <1year if the diffrnc is greater than 1 year

I don't understand. I assume a typo. However, I recommend you use the Formulas->Evaluate Formula option in Excel to see how the formula works. I think once you see it in action, it is easy to understand and modify to your needs.