I would just keep to the same scheme as your breakfast, making sure you stay at around 400 calories pr meal with with 85% of those coming from fat. I am sure you will start seeing benefits. **Make sure to drink a lot of water too** and watch that you are having enough salt – get a good mineral salt, or eat something with enough magnesium. My dad started this diet and he is 85. After about 2 weeks he is a different man – more energy, and better sleeps.
While macros will differ a little from person to person, the general rule of thumb for keto is to keep carbohydrates under 5% of your daily caloric intake. As long as you avoid the foods mentioned above, you should be fine. Google “TDEE calculator” if you need some additional guidance on how many calories to eat. I’ve had success following this way of eating as it allows me to eat foods that taste great. There are tons of resources online as well if you need additional guidance. A quick google search should turn up a ton of resources. Hope this helps!