Grow account with 2 Subjects

Hi,

I'm new here and it's my first topic.

I've a personnal account with two principal subjects : Food and Travel

I want to know if it's not problem to have two subject in one account ?
How can i construct my hashtag if my picture contain differents topics (3 importants likes : restaurant, rome, hamburger) ?
Can i increase the real followers with 2 subjects ?

Thank's for all