I’m glad it has holes drilled… that’s the downfall of most tumblers.
If you’re looking to do this with less labor, just take the barrel and sit it straight up- cover it with 3/16″ holes. Forget the tumbling aspect, just start it with 12″ of shredded browns, then with each deposit of food scraps, add double the amount in brown materials.
By the time that fills, you’ll have compost on the bottom.
The easiest option is to have a second one to start filling while the first one finishes… doing this, you’ll have a great back-and-forth system to work with.