I raised my 4 kids at a time when we were recommended to start giving cereal(s) and juice(s) at 6 WEEKS (not months). All was well except one child (I think) had food allergies and I didn't know about the 'introducing one new food at a time for a week before adding another'. Anyway, now we have 3 grandkids, the youngest of which is almost 10 months old. Our daughter is very particular about what she feeds them, but it doesn't have to be complicated. Go with your instincts. Think of all the babies who've ever lived in all times and places who've had to eat whatever was available to their families (rice, potatoes, eggs, pumpkin, etc) -- and they survived! LOL
Cook some veggies yourself and run them thru a blender or small chopper (God's greatest gift to mothers!) with littlr or no salt, sugar, fats, or seasonings as you prefer.
Probably should mash banana, as a chunk of slicky banana could easily get stuck in a baby's throat. Some of the most common choking hazards are whole grapes, hot dogs, peanut butter, etc, so just think before you give it to the baby, 'could she get choked on this?'
You'll do fine, as will your daughter. Only make as big a deal of what (and how much) she eats as you feel is necessary. My mother insisted that we always eat everything on our plates, then when I was an adolescent and grew like a weed, she made comments that I was eating too much/growing too fast. This led me to anorexia (before our country doctor had ever heard of such a thing), and it was pretty traumatic for all of us. I've always just told our kids to eat til they're full and stop, pure and simple. The 2 girls (31 & 20)are average size, one boy (almost 23) is rather heavy (and has always loved sweets), and one (28) is thin (and never did like sweets! This is the one who had some kind of skin rash as a baby).
There aren't any 'hard and fast' rules nor any guarantees about rearing babies, so just enjoy that little one and train her according to your values, ethics and priorities. That's what's most important!