It actually depends on the softwares that you are going to use... By writing I assume you'll be using word or PowerPoint or you might use it to write for a blog online...
1. I recently bought a Lenovo IdeaPad s145 for my mom. She wanted to take online classes and make forms...
This laptop was perfect for her. It is a bit slow but if you are patient enough then it gets the job done... Costed me a little over 21k...
2. If you are not constrained to a budget then I would say go for a macbook air 13inch i5 5th gen. Would cost you between 50k - 65k
3. This has to be the middle ground.. Asus vivobook core i3 10th gen with 256gb sad
It has speed and is light weight and not to harsh on the budget as it costs around 36k on Flipkart