Looking to learn. Questions within Roth IRA

I am currently only invested in VOO and SPY within my Roth IRA. Just looking for help, I’m really trying to learn here. Here’s some funds I’m looking into: Large cap- FCNTX, AGTHX Small cap- OPOCX, NESGX, OMCIX Tech heavy- FSPTX, FSELX I understand these are mutual funds and I’m trying to figure out if I do add some of these more risky funds how does that work within a Roth IRA? What does portfolio turn over matter within a Roth IRA or even expense ratio? Until I figure it out I’m just going to