Help Understanding My Mutual Fund

Hello, I was given a Vanguard Mutual Fund (Morgan Growth) as a trust a long time ago. I'm just now beginning to research investing and finance in general. I'm wondering what exactly this fund is, or how it works? Depending on smart choices, is it worth while taking most of this money out and reinvesting it in other businesses I deem worthy and actually understand ? This fund shows a 12.8% rate of return which seems pretty good. Perhaps selling some of it while it is relatively high, and buying more at a later time if it gets low. But again, I'm very new to all this, so a lot is still quite confusing. Thanks in advance for any input regarding this matter