This is a very simple idle game with really only 3 mechanics. One is the mining screen which after a short initial phase consists of one expensive upgrade every few hours that drastically increases your money gains. The second is workers which gives you money every few seconds. They will soon be obsolete since they don't scale with mining upgrades. And finally reaserch which gives small buffs if you pay some money and materials. They may seem insignficant but here is the real end game. Getting to level ~5000 for 3 different upgrades. This requires constant micromanagement for I suspect about 10 hours constantly dealing with storage space issues since you can't store up materials for more than 2 upgrades at one time. There's probably an autoclicker solution if you want to have the game running constantly for I suspect like 2 days just getting storage upgrades. I'm not comitted enough to go through this chore to give you an actual time estimate.
1.5