Easiest way I can load up a FEN and play out a specific situation against a very good computer?

Is there any way that chess.com would prefer I do this, like can I do it while I have chess.com open etc?

When I tried to do it in the way shown by Kesoto at post 3, it didn't play back if you know what I mean.

I would just copy the FEN (via share/download usually, but there are likely other ways too), then go to chess.com's "analysis" (under "Learn"). Then all you need to do is paste the FEN where it says, click "Load" and you should be set to play out the moves from there. Additionally, you are in "analysis", so you can also play any computer level from this position too ("play computer" by the bottom right icons near "analysis", "download" etc.)

wow! thanks so much Kesoto am very glad can do this on this site.

It did not indeed. At least it didn't finish with the first four letters of analysis this time!

Basically got told NEVER do this joke again we do not give advice on good analysis (- 4 letters.)

"Then all you need to do is paste the FEN where it says, click "Load" and you should be set to play..." and I don't see any Load button. Help!

The UI has changed. Now after pasting the FEN, you click on the green "Add Game(s)" button.