I started using my own compost for potting during Covid, when I hadn't got any, shops were closed, and it didn’t seem fair on the delivery guy to order online. It would probably be better to add soil, but I don’t have any accessible soil in summer.
I’ve made compost for >30 years at this garden. 3 bins, one having stuff added, one maturing, one emptying. I think it’s developed a good range of bacteria and fungi, it certainly produces good compost. I don’t turn it, except when I’ve emptied a bin and dump the unrotted stuff on top of the next bin into it.
Weeds (all my weeds are spread throughout the garden anyway, so I don’t worry about roots and seeds), grass cuttings, soft prunings, veg waste, tea bags, coffee grounds, tissues, soft paper and card, bones once they’ve been well boiled for stock - anything compostable.