@adithyanwarrier lagging and getting slow how? Slow to function on start up or slow with the programs etc. Could be an issue with your storage i.e. HDD getting full and "congested" Could also be an issue with your OS. Windows is a hog when it comes to collecting files etc. I'd consider updating the storage (if it has a HDD change it to an SSD) and maxing out the memory. Reinstall or at least clean your OS files as well as system files.
You did not tell us all the specs for your computer. This is pretty general but it should still get you going in the right direction.