Determining price is always difficult, as it depends on a lot of different factors. Your level of expertise, the time you take to make something, the demand for your kind of work, the cost of living where you are etc. As a rule of thumb however, I always recommend that if you can not sell your work at at least your country's minimum hourly wage, you're not ready to sell yet.
As for how to get commissions, that's a matter of marketing yourself. Probably the most important factor is your activity. Pick a place that is highly trafficated like FA or Twitter, set up your gallery and start posting work. Reply to comments, thank people for following you, interact with other artists, join art streams, hold raffles, create gift art, do YCHs or themed work, - anything that might entice people to follow you because every new follower is a potential commissioner. If you start posting your work on other sites, always be sure to link back to your "main" gallery. This gives you a centralized place to start taking commissions from (rather than having to cross-post).
You only have one picture in your gallery so far but I like what I see there, you seem to have a pretty fun style. Post more and keep posting.