Unless you have a set time you're wanting/needing to lose weight I'd suggest not to go really hard at the start. A lot of the time when people jump in and go as hard as they can but end up burning out or quitting so far in. It tends to make exercise pretty miserable that way too.
Depending how in shape you are would change my suggestion of how much, for how long, and what to start with.
HIIT exercises tend to be one of the fastest ways to lose weight. But if you're VERY out of shape that might feel like too much. In that case some simple ones, walking etc to build some strength and stamina to start might be better.
Before and after you exercise, stretch!
Eating healthier is best, but you don't need to go full on vegetarian. Unless you really want to do that.
If you don't know what your BMI is you might want to look that up. It will give you an idea of what your target zone should be. If it's a huge gap, it'd be all the more reason to give your body time to adjust to the new changes.
_________________
"Inside the heart of each and every one of us there is a longing to be understood by someone who really cares. When a person is understood, he or she can put up with almost anything in the world."