I am a beginner on baking cakes, at first it was just meant for family but now I do have a couple of friends and friends of friends starting to request cake from me. I am nervous as to what to charge. I usually make basic cakes so far, plain yellow cake with buttercream icing. It did take me a while to do this cake but I am thinking it is because I am a beginner. Thank You in advance!

Your pictured c ake look really nice.  Yes, there could be a few improvements but overall for a beginner  it isn't that bad.

Pricing is very hard to quote.  There are so many different factors to consider - including your location.   You will get lots of people telling you to add up *all* your costs, including an estimate of how much electric/gas/water used and how much you want to 'earn' per hour.

I suggest y ou do spend some time figuring some of that out but as a starting point go with a basic pricing of *no less* than $50 for that size cake.  I know - it sounds like a lot but once you do the figuring you will soon find out why.

Check out other pricing threads on this site for more help/suggestions. 

Here's one thread that will help you some:  http://www.cakecentral.com/forum/t/824132/cake-pricing

If you're going to get into actual business you will want to investigate the laws that pertain to your city and county as well as copyright law.  We don't want you to get into any trouble!