Greetings!!

I know that this is off topic but I figured that people who build things
with their hands would have some ideas on installation replacement windows
in my house.

I just got a quote from Anderson windows (and about had a stroke). Further
research indicates that it is possible that I could do a replacement myself.

But, I dont know where to buy replacement windows. Are they at Lowes and
HD? Do I order them? How do I get them to fit my openings?

I am overwhelmed by sheer number of choices (analysis paralysis) and any
help you could offer me would greatly help (and possibly save me money that
I could spend in my shop on new tools!!).

Thanks again.

Rob