Can I connect the RO system to my kitchen faucet?
The short answer is no.
Keep in mind that the RO water available for use at full pressure is the amount of water in the storage tank which is typically 3.2 gallons. The kitchen sink typically dispenses that water at a rate of about 2 gallons per minute. In the real world you will frequently run out of water.
The RO system can be physically connected to the kitchen faucet, but once the water in the storage tank is used, you will be left with only the RO system's production rate which is a trickle (50 gallons per day, or 2 gallons per hour). If the kitchen faucet is at a secondary sink that is only used for drinking and cooking water, such as a bar sink, then it is suitable.