Wordpress + Phpbb should be the right solution for you. If you mix it right, it will be powerful and has many rich features for you to use and the best part - they are both free (unless you go for premium addons/plugins/themes).
If it is a small website (and it should be for starters) - Get a low cost shared web hosting, it will do the job. Don't forget SSL certificate, most web hosting services now offers it for free via Let's Encrypt, so don't be tempted to buy one (prices can be $50/y). When your forum will start growing (I cross my fingers for you) do think about moving to a VPS, but you should read and know how to operate and maintain it.
Setting up the forum is the easiest part - running a forum (or a community) is difficult, gathering people to be a part of your community could be though and can take months and years. Try to locate the right contributors to promote, be fair and try not to enforce your opinions or ideas on others.
Good luck!