Keto diet and weight loss

I have approx 25 lb of weight to lose. I have lost 60 pounds in the past but have put it back on. When I lost the weight I remember I had gone low carb < 100g and I lost weight. I seem to have already hit a plateau on weight loss. right now I'm just monitoring my calories and macros eating about 1800-2000 cal daily. Would you reccomend going low on the carbs to see some results or just going full kept. Also about the keto diet how low should the carbs be, how long till I get into ketosis, and how long should I do the diet for before I start compromising muscle loss, last would you recommend refeed days on the keto diet? Thanks marc