a 10+ year old dual core is going to struggle in most all modern games....
A better GPU will allow higher resolution and texture details, but, the top frame rates available from even the GTX1050Ti (essentially a 60 fps at 1080P card on medium details/quality) are likely not yet being achieved currently.
A GPU upgrade now will likely still leave you stuttering/hitching in heavy action sequences, as certain portions of many games require enough CPU to maintain minimum FPS.
I'd be looking for a CPU/mainboard/RAM upgrade, and, if your PSU is from the same era, a new PSU as well....
(AMD's budget 3300X or 3600 both offer outstanding framerates for $120, with B450 mainboards avaiaable near that same price, and, 16 GB of DDR4/3200 MHz...