Welcome to Kuala Lumpur. One day is too short for you to explore KL and the outskirts. Come back, stay longer and explore other places like Penang, Malacca, east coast of the peninsular or fly to Borneo part of Malaysia visit Kuching or Kota Kinabalu, etc. For EU, UK, Canada or US citizens, can stay up to 90 days in Malaysia without a visa.