Dear Shefali,
With small activities, you can break the monotony. Every morning, you could send a mail with greetings or a nice thought. Consider having short games for half an hour once a week or every 15 days. Additionally, you could organize a monthly birthday celebration for all employees born in that month (budget permitting, a small party or just a cake will suffice). Internal contests like photography, drawing, rangoli on Diwali, etc., could also be engaging.
These are just ideas. As you know your company and employees best, create your own approach and do share it with us so we can also implement it.
Thanks & Regards,
Pranali G