>>1892303i was writing a guide but /n/ has become so infested with consoomerism it's not really worth it.
basically try to find a used ATB bike AKA "90s mountain bike" which is usually a steel or aluminum ridged (no suspension) mountain bike/hybrid , something like a bridgestone mb-5 as a "this is what I should look for" kind of model. Check facebook market, check creigslist , check local whatever u have, if you have a bike shop that sells used bikes check there too. 5'9 means probably most mediums will fit you fine, which is a good height range to be in.
I don't go fishing but I take my gf out to a grassy knoll 7 miles out and we play board games and picnic every weekend or so. And something like pic related works great for that.
When you go to look at used bikes make sure you go through all the gears and the brakes work. Check the frame for cracks or anything else bad, make sure the wheels arnt dented or bent to shit. Most of the time iv found with used bikes is that you have to buy new tires with them so budget that in. if you have any other questions just reply to this post. (or your mother will...)