Seems normal, why do you want to change it? To change it you would need to re-install Windows if your motherboard can even work with GPT. That is an old laptop, I'd leave it as it is since it's working now.
You can’t reinstall W10 in UEGI (GPT) mode because there is no possibility to define UEFI Boot option. This laptop is old, but strange there is no such possibility and BIOS seems to be of UEFI type (GUI, mouse support etc.). Despite being old, it is still very well doing with top OS and SSD, performance very good.
The same „old“ laptops like e6400 (same chip technology, same CPU, motherboard) can do it.
I would like to fully exploit it before declaring as old, this is my motivation.
Besides, I have changed the stand art from MBR to GPT for all my HDD/SDD/NVME so this is the another reason to try UEFI boot at e6500 (even if modding of A29 must to be undertaken-or someone already did it). Regards