She does look a bit squared.
But the gravid spot doesn't seem very dark. When it is very close you might be able to see the eyes of the babies.
To prepare for a delivery, you may just let her out for now, and then at a point you'll likely see her hiding in the plants or at the top in a darker area.
If you can get some healthy looking stem plants from a store, the type which come banded together. Ask the employee which plants grow like weeds in your water /area in the aquariums.
I would gently rinse them in some old water change water, swish them around. Let them loose and float at the top of the tank for cover.
You can add in fake/ plastic aquarium stems if you have no other option. Something is better than nothing.
Do a series of pwc
. How much are you doing right now - do you change water every week?
If so do 2 of these water changes, one after another - say if you do 25%, then do one 25%, then refill and another 25%. The next day do another.
You want to get the water freshened up and really clean as you may not change it very soon after the babies arrive. They are very small.
If you have a vac tool, use it to do the water changes and clean up.
Give the filter media a gentle swish in some water from the top of the tank (cleaner than the mucky stuff at the bottom).
Do you have a HOB
/ hang on the back filter? If yes, while you are at the store find a sponge cover / prefilter for the intake tube of the filter. This helps prevent babies from getting sucked up.
As that female looks very much to be an adult, with males, she should continue to have babies every appx. month. Even without males she could still have babies for appx. 6 months.
This is to let you feel more comfortable that live bearers will have lots and lots of babies, because in nature they are eaten by predators. So some survive, and then there are more babies soon, etc.
I always drop in a little food on the opposite side of the tank from the moma, to help fill up the fish when momma in birthing. Then a little bit near her in case she needs food for strength. Some are not interested in eating and some are ravenous. Feed her a tiny bit at a time if she wants to eat.
If you need to you can put the 2 males in the container to separate the fish.
Soon you will have many babies.
I usually use Hikari Fry Food, or Dwarf shrimp baby shrimp food. Last year I had over 2 thousand / 2,000 Guppies and Endlers.
Mainly I keep males now. Too many
guppies / Endlers fish!!!
Change the water 2 times or more often because of the tiny food. Be careful to not just dump in too much food at once. And babies like to eat a little several times per day.