I need to incorporate a payment page in my website (credit card with shopping cart)

Please contact me as soon as you can.
I have 2 issues. I am making a simple website but I am not a professional
The first is very easy (for you). A few things that Can be done in an hour. For example I want to have compatibility in all browsers and when I minimize the window of my website the items of the menu don't stay in place....I also want my content to fit in any size's screen and not have to scroll horizontally to see the content. I know my css file has some issues. there is the problem.
The second and important thing is to have a e payment page in my website (credit card with shopping cart)...I am leaning towards a ready to use software like spicelogic (my budget is very very low)

I can give you privately my website's URL
Thanks