Ive been planning, and slowly learning about beekeeping for a year, and a couple days ago my neighbour out of nowhere my neighbour said they will keep bees too. Is this something that could possibly have an affect to the bees?
We are spaced apart ~300m


no, they will be fine generally.
to put it into perspective a 300m radius circle has an area of ~28 ha, if both hives fly that distance 56 ha less the overlap, say 1/3 the area rounded up to 20ha, that still leaves in excesses 36ha for the bees.
In New Zealand it’s considered fair summer coverage for upto 1 hive per ha
Thank you!