I think many homeschool moms feel this way about high school too (it's going to be SO hard! can I do this?!) - and many give up before trying - that's why I'm doing what I'm doing on this platform! It's just the next step.... there is more recordkeeping, but it's doable!
I think Oh Freedom is more geared for middle school specifically. When we used it my girls were just too young to understand it. Our History HIS story the elementary level has more for the younger ones. My older girls enjoyed the readings as well but we did add a little more detail for them. Oh Freedom does have an elementary level now. I’ve not ever used it but you may check that out. I believe you can get a sample of the first lesson or 2. Also Our History HIS story has a specific middle grade level available.