If you want to lose weight, the best way is to consume as much information about proper diet as possible. That new info will cause you to find a way that works best for you.
For me, intermittent fasting and low carb became my best strategy. I lost 160 lbs in 2 years after age 50. I lost approx. 8-12 lbs. per month.
There's no way to say how long it will take you. My best advice is to weigh every day, but don't be too concerned about 5 lbs either way. You can fluctuate that much each day. What you want is to track is the trend over 1-2 weeks whether you are slowly losing weight, staying the same, or even gaining, and adjust what you are doing accordingly.