There are individuals who get strong quickly, learn proper exercise form instantly and effortlessly, those who stay lean easily, those who seem to get lean with ease. Then there are those who must be extra diligent and more disciplined. Strength is harder to gain. Building muscle is a struggle. Losing fat is no easy feature. Keeping fat off is even more challenging.  Are you the type of person that gains weight easily and must work harder than your friends/family to lose weight. As much as that sucks for you, its your reality. Acknowledge it, embrace it, and keep charging forward. Don't allow the challenge to be an excuse not to become the best version of yourself. 

Some days or even spans of time, you will not want to workout. Or your schedule will be unpredictably chaotic when getting in regular workouts is a challenge. It'll be up to you to do it anyway, in whatever capacity possible. Motivation is not always abundant, and neither is time. But don't let this dishearten you. Simply accept it as a fact of life, and then have a plan to deal with such situations. When things are good, take advantage. When your plans get wrecked, find a way to work with what you have.

Just because it worked for your friend/family member doesn't mean it'll work for you, this applies to diet and fitness. Your friend/family member swears by there bodyweight workouts, but you may enjoy and respond better to squatting, deadlifting, and pressing progressively heavier weights and using bodyweight exercises to complement your barbell training. Your friend/family member swears that skipping breakfast helped them shed those last few stubborn pounds but skipping breakfast may mean struggling to get through the first part of the day for you.

Everyone is different. Pay attention to how your body responds, and don't be afraid to take a different path. It's your body - be your own.

Many will sorta kinda try a diet for a couple of weeks and when they don't look noticeably different, they blame the diet and exclaim, I knew that was too simple to work but in reality, they did not do it. Either they practiced the guidelines sporadically, or didn't do them long enough. Don't look for something complex or advanced until you master the basics. I mean doing the proven things - eat mostly real food, eat sufficient protein, make sleep a priority, strength train at least 2x a week - for many months. Be honest with yourself; are you doing the things you know are important, consistently? If not, how can you change that, starting today ? 

There is no best diet, only what's best for you, don't allow dogma to cloud your judgement.