Keira, the BEST way to learn to sew is to just plunge in! Really. You could start making pot holders or some other straight stitching, simplistic item but you will quickly get bored because there is little challenge there. Think bigger (without obsessing about your lack of skills) and allow yourself to stretch.
For example, I'll bet there are children in your ministry who NEED something made out of cloth -- shorts, an art apron (to protect their good clothes while they finger paint or play with clay), a T-shirt, a baptism dress, a loose fitting jacket. Kids don't stay the same size long enough for you, their parents or the kids themselves to worry about some little "flaw" in technique or shift in fashion sensibilities relating to fabric (polyester vs. 100% cotton), color, or style. Kids' clothing takes less fabric -- so you could harvest fabric from thrift-store finds or used adult clothing and rework it into something a child would love. Any garment or portion of a garment (like a bodice, a yoke, sleeves) can be cut out of patchwork (make your own fabric by stitching bits and pieces of fabric to a foundation fabric like an old sheet following the instructions for foundation piecing/paper piecing) --- yet another way to minimize the expense of acquiring fabric.
The delight your little friend experiences when receiving your unique gift will inspire you to do it again for someone new -- and learn some additional technique while polishing the skill you developed the first time you took the plunge. After you've made a few things, you'll have a lot more confidence than you have today in your ability to master sewing skills.
What you learn making give-away kids' clothing is completely transferrable to other projects when you feel ready to try your hand at something for yourself. Best of luck!