Newbie

Welcome!

I would suggest reading some of the most helpful threads stickied at the top of each subforum, for example:
https://community.myfitnesspal.com/en/discussion/10300331/most-helpful-posts-getting-started-must-reads
https://community.myfitnesspal.com/en/discussion/10300319/most-helpful-posts-health-and-weight-loss-must-reads

Aside from that, I'd like to offer this advice:
- take things one step at a time. Sustainable weight loss takes lifestyle changes and habits are best changed gradually to allow them to 'stick'.
- Weight loss is not linear. Look at the long term trend, don't panic if your weight sometimes goes up.
- Don't make things harder on yourself than necessary: don't choose an agressive rate of weight loss (slower=more food=less hunger), don't force yourself to do exercise you dislike (the best exercise is the exercise you'll actually do), don't eliminate all of your favorite foods (learn to fit them into your calorie allotment). The easier you make it on yourself, the more likely your new habits will stick and the less likely you'll give up.
- weigh your foods (it's more precise) and make sure you're using accurate database entries (the database is crowd-sourced, there are many wrong entries)

Also, being active in the forums (or even just being a lurker) is a great way to absorb knowledge. And feel free to ask questions! Lots of people here willing to help.

Wishing you success!