The Moxie mentioned upthread is within about 20 minutes walk of Dennistoun.
It's a perfectly easy 30 minute walk from the city centre to Dennistoun and you pass the Tennant's Brewery, which has a bar and restaurant, and the Necropolis - you can't unfortunately cut through it but it and the Cathedral are worth seeing.
There used to be hardly anywhere to eat in Dennistoun itself (I moved there 25 years ago!) but quite a few places now and some of them do vegan food. Nakodar's been around for a long time, and there are several others. I'd check out Celinos to see if it does vegan food.
If you're there over a Sunday the Barras can be fun, it's a lot less rundown than it used to be and has moved into more trendy, bohemian stuff than it used to offer.
If you're going out for breakfast on Sunday in Dennistoun, particularly Coia's, you'll need to book.
Glasgow Green can be lovely but the main draw there, the People's Palace, is closed for a refurb.
The buses are frequent and a Number 38 will get you from town to to Ally Parade, but the buses also poor information for non-frequent users, and are a bit incomprehensible to tourists.
Train wise, there's no subway as such in Dennistoun, this gets mooted before every election though so maybe one day.
The trains that do exist are the "low level", they run from the platform below the main concourse on Queen Street. Bellgrove - which you're almost as well walking too - is the most frequently served station. Duke Street and Alexandra Parade have less frequent services. They're on a less busy line and if you're aiming to get to one of them, be careful the train you are on stops there and not Carntyne, which is a couple of miles out in a residential suburb.
You can get trains on this line from Patrick, but not from Central.
Dennistoun to Partick is easy but other bits of the West End will involve changing to a subway train or walking; I wouldn't recommend it as somewhere you can get in and out of Dennistoun quickly.