Possibly the most intimidating thing for any beginner is simply getting started onto the path of healthy eating and proper exercise. Once you're over that hump and an action plan is in place, then you'll find that your main focus turns instead to maintaining motivational levels and ensuring that you stick with that program.
Having the program in place though needs to be the primary focus initially since it's going to guide you down the path to your goals. Here is some information to get you started.

WHO YOU ARE AND WHAT GOALS YOU HAVE

You're someone who might have dabbled in the gym many years ago but have taken an extended time off or someone who has never even set foot inside the gym for a workout. You're new to many of the concepts of what a proper program consists of and are like a sponge, soaking up new information.
The primary goal you want to focus on at this point is fat loss. You might have some desire to also work on building your muscular strength, but that will come down the road once you've stripped off the extra layers you've packed on over the years and are starting to feel leaner. You want a plan that's going to be easy to follow and will get you results quickly.

YOUR SOURCE OF MOTIVATION

Motivation for fat loss can come from a number of places. Perhaps your doctor has instructed you to drop a few pounds because of your current risk for diseases or other negative health impacts. Or, maybe you have finally had enough with your current body weight and have decided to take action to reduce your weight down to where you feel comfortable.
Some people are also primarily motivated by the thought of having more energy after losing weight and getting active, so this could be something else at play for you. Finally, others simply want to look better.
Whatever your source of motivation is, it's important at this stage to pinpoint it and always keep that in the back of your mind as you progress along.

YOUR NUTRITIONAL PROGRAM

As a beginner, what you want to mostly focus on right now with your nutrition program is making small changes on a continual basis to help improve your overall diet. If you attempt to completely overhaul your entire menu, removing all the foods you typically eat and replacing them with chicken, rice, vegetables, and other standard '100% healthy fare', you might find it becomes too much and you're overwhelmed.
Instead, incorporate in more of those healthy foods, while reducing back on your unhealthier choices. As time progresses, start tilting the scale more in favor of solid healthy food choices, while limiting the processed, refined, and higher calorie items. This slow elimination process will be much more doable for you than trying to quit cold turkey.
One thing you do want to start doing at this point is making yourself more aware of the total amount of calories you're taking in on a daily basis. While making healthier choices is incredibly important, if you're still eating too many of those healthy choices, you're not going to achieve your goal of weight loss.
Find an online calorie calculator and start plugging in the foods you typically eat. Then get your measuring cups out and start finding out exactly how many servings you are eating in a normal meal (do not skip this step because serving size will make a dramatic difference on fat loss).
Do this for about two weeks until you gain a better understanding of your total calorie intake. At the same time, try and educate yourself about how many grams of carbohydrates, protein, and dietary fats are in the common foods you eat as well.
In terms of your calorie intake to shoot for to get fat loss happening, aim for about 12-13 calories per pound of body weight if you're active and 10-11 calories per pound of bodyweight a day if you're not. This is a simple way to estimate your fat loss daily calorie requirements.
Out of those calories, you want to aim to get about one gram of protein per pound of body weight. So, take your current body weight in pounds and multiply by four (the number of calories that are in one gram of protein). This is how many total calories each day should come from protein foods.