Tim Ryan doesn't actually have an issues page but he has some stuff on his homepage.
According to his responses to the New York Times, Ryan supports single payer. However his responses and his website say that we need to be "realistic on how we get there" which sounds like he actually supports public option in 2020 and would go for single payer later.
His website acknowledges climate change and states that we need to lay out a "pragmatic, climate-conscious energy policy" to get us to a 100% carbon neutral future. However, he's a congressman and he could co-sponsor Alexandria Ocasio-Cortez's Green New Deal resolution, Here's the list of co-sponsors on her bill, Ryan isn't on it.
According to questions from 538, Ryan does support marijuana legalization.
His website does not mention anything about campaign finance reform or breaking up monopolies.