How much protein

What's your goal weight?

The MFP defaults aren't a terrible starting point, as long as a person doesn't try to lose weight too aggressively fast for their current body weight and calorie needs. (There's no getting adequate nutrition on too-few calories!) A common rule of thumb suggested here is to lose no faster than 0.5-1% of current weight per week, with a bias toward the slower end of that unless severely obese and under close medical supervision for deficiencies or complications.

I'm not saying you shouldn't adjust those macro goals to be different from the MFP defaults; I'm suggesting that the high priority is to start logging current eating and seeing how that stacks up in calories and nutrition.

You don't have to perfect your eating routine instantly. In fact, if your primary goal is fat loss, calorie level is the prime determinant of that, so a good place to focus first. Macros aren't directly key to weight loss. Yes, nutrition is important for health and energy level, so it can affect weight loss indirectly through fatigue or appetite.

There's a research-based protein estimator here, from a site that's generally regarded as neutral:

https://examine.com/guides/protein-intake/

Note that the guide portion of that suggests that it's OK to use goal weight in the estimates if currently substantially overweight.

A common rule of thumb for fats is 0.35-0.45g minimum daily per pound of body weight (can use goal weight if substantially overweight), though men might get away with a bit less, maybe 0.3g/pound. (0.35-0.45g per pound is around 0.77-1g per kg.)

Protein and fats are "essential nutrients" in the sense that our bodies can't make some of their necessary components out of any other food intake, so we need to eat some. Carbs aren't essential in that sense, so can be adjusted to balance calories, or according to how they affect a specific person's energy level and/or appetite.

Don't let these technicalities bog you down. Any choice you make now (such as starting from the MFP defaults, or something else) can be adjusted as you learn more, and there won't be some huge scary bad thing that happens from being mildly sub-ideal for a bit. Humans are adaptive omnivores. As long as not starting with a diagnosed deficiency or diet-relevant health condition, you can take a bit of time to learn and fine-tune. (If a person does have a deficiency or relevant health condition, it would be good to consult a registered dietitian for help.)

Best wishes!