Blackberries, raspberries, grapes, etc all set fruit a.most entirely on 2nd year canes or vines. So what grow *this* year will not generally make blooms or set fruit, but if you can keep them alive another year, you'll get some fruit. The year after you'll get more. After that the original canes will die back, but the younger ones will go on, and new ones will spring up. IOW, branches make fruit on a 2-3 year cycle, then die off while younger branches take over production.
If they aren't in the way, let them grow. But don't put much effort into them. They may be good, but likely not.
A lot (most) commercial plants are F1, and won't seed true.
If you want to plant berries seriously, find a local grower with plants adapted to your area. Get starts, not seeds. And if thornless is an option, take it.