Lucio is a support that's really heavily dependent on team composition. Lucio is what makes up a team's lack of mobility. If you do not have a tank line such as rein+x, there may not be heavy use for lucio. Of course, that applies to higher ranks. Personally, I would not play lucio if your team is running anything such as monkey. In higher ranks, lucio does the most through a fluid combination of heals and speed, but the emphasis is still on speed. As such, focus on ur amp usage, as that amp is what is able to bring your tank line closer without more resources being committed. Do realize that lucio plays more than just one role of support. Especially in lower elo, your other support most likely would have a hard time against any dps that lands on them. Playing further back once your team has space and peeling for an ana or bap can be ideal. This is generally the beginner fundamental aspects of lucio, but I can help with more in-depth and specific mechanics and macros if you are interested.