You need the services of a local design professional. Contact one ASAP. There are hundreds more design related decisions to come.

I agree with hollysprings, a designer to help coordinate all the many decisions coming is extremely helpful.
I'll tell you what we decided, and none of it is installed yet, so I don't know how it will actually look yet. We matched the windows, doors and trim, (we did stained). We picked cabinet colors we loved that harmonized with the windows, doors and trim and the floor will probably be lighter, tbd after all the windows, trim, doors and cabinets are installed.
Take a peek at the Houzz site and you'll find lots of pictures with details. This can help you decide what you like and want to emulate. Good Luck

Our interior trim and cabinet color match. We have white windows and matched the paint color to them

The early stages of design are always a bit overwhelming. So many choices and you can feel this burden to "get it right".

You are dreaming of an off white kitchen - great! Now, think about how it feels to stand in the kitchen. Where is your traffic flow from outside and to the dining room? Do you want a large open plan? Or more defined rooms with doorways?

These are the types of questions you need to focus on now. Shades of color really should be the last thing on your mind (as tempting as it is to dream of them). Think about your family, get specific about what you need, make a separate list of wants, and spend your time creating the spaces of your home.

This is what an architect does. You may need one, or you may not. I got caught up in details when we started our design process, and my DH had to remind me to focus on the big picture, not the details.

Houzz really is your friend at this stage. Just go through and click everything you like. Soon, you'll see patterns emerge, and you get a real sense of what speaks to you architecturally. From there, you can search plans online within that style. Lots of people have already done a lot of planning and hard work, and there really are some good plans out there to use and learn from.

As far as your original question, I think the interior trim will have a much greater impact visually, than the actual window. Will your cabinets be directly next to your window?

If you have a plan you are working on, you might get more help if you posted it separately for overall design feedback. Good luck!

Our cabinets and trim are SW Alabaster - they're not an exact match to our white windows (Marvin Integrity), but look nice together, IMO.

We had painted white trim, doors, windows and off-white glazed kitchen cabinets in our previous home and it looks great. I don't think I would like off-white trim throughout a house just to match the kitchen cabinets, but that is just my personal preference.

We ran into the same dilemma in our new build. The windows and extension jambs were pre-finished and the cabinet maker didn't have the same white. We debated on getting the windows unfinished and painting or paying extra to get a custom color for the cabinets. We ended up doing white cabinets with a glaze. This way it looks as if it was planned not to match. The only place that you actually see it is the kitchen window and to me it looks fine. If you go on houzz and do a search you will come across plenty of photos with different cabinets and trim color.

There is no need for your kitchen to match your trim, IMHO. Many homes have wood kitchens and white trim and look great. Others have creamy glazed cabinets - and bright white trim. Looks great.

Thank you everyone for your help - I appreciate it!!!

Agree, it doesn't matter. In fact I love mixing it up and think sometimes it looks even better when you do. Fwiw, our cabinets are off white, our trim is off white and the window frames are like a more beigey color. But, our walls are a bright white. I love it!