Which Monitor /Display for my microscope camera? Or new camera?

[Noy]

Sorry put the whole text through Google Translation...:

So:
I have a 13MP microscope camera with an 8 "800x600 4: 3 display.
Now I'm not entirely happy with it. The camera has HDMI and VGA out.
Apparently I can switch between 1024x768 (VGA / HDMI) and 1280x1024 (HDMI) at the push of a button.
At least that is shown on the connected display.
Now I have several questions for a better understanding:
There are now also cameras with 38MP from China etc. The 38MP are probably photo resolution. As a video, the often 1920x1080 @ 60fps some also have 2k @ 30fps.
Are they great better than my current 13MP and the information does not match the 1280x1024 etc.
I mean what do the 38MP bring if they mostly run in video mode and therefore "only" deliver 1920x1080?
Sometimes I have to take pictures of solder joints for work. Unfortunately, an HDMI / VGA grabber costs significantly more than I want to spend.
So either I buy for 70 € from china a 38MP camera which now has a uSD slot or USB connection to sometimes take the pictures.
Alternatively, I would want to replace the monitor and could take a picture of it if needed, but would also have a better "live picture" in general.
Now the higher resolution 1280x1024 is a 5: 4 resolution.
What is the best way to buy a monitor? Would also like to upgrade directly from 8 "to 10.1". I have now ordered the following from Amazon:
https://www.amazon.de/Eyoyo-Monitor-1280x720-Display-Sicherheitungssystem/dp/B07G54M779/ref=sr_1_19?__mk_de_DE=%C3%85M%C3%85%C5%BD%C3%95%C3%91&keywords = 8% 22 + eyoyo + ips & qid = 1585352705 & s = computers & sr = 1-19
Looks much better and has 1280x720 but is now smaller than my old 8 "with 4: 3 ..
So I'm looking for a 10.1 ". But which resolution fits best?
10.1 "with:
1024x600 1280 x 800 1366x 768/1920 x 1200?
Would definitely take an IPS with> 400cd and the highest possible contrast.
Advantage on the new monitor, if necessary, it is used to quiet children while on vacation.
Pictures once old 4: 3 and once 8 "IPS.
What does an image from the camera (1280x1024) look like on a 1920x1200 display?
Can it look worse because of render / convert?