1 – Can impact reference or Background Check as normally it goes to reporting manager
2- Varies company to company (During notice period leaves are not allowed – except sick leaves)
3- You must be getting leave encashments of those 50 days. If not, talk to your HRBP.
4- they can terminate you during notice period also.
But as you are on notice period. Just try to get an easy exit. All the best for your next endeavour.