What can they do to ensure that they make profit?
Build a nuclear fusion plant, sell that electricity to the grid, profit!
There is no way to ensure! profit, you either have the conditions in which most likely you will make a profit, which means nearly free energy, zero or low tax and vat on imports, hefty state deductions, you own the space you're going to mine in, or, you start without one or two of those and you go up the ladder of risking to not make a profit at all.
Mining is one of those businesses where no matter your skills or your knowledge if the cheap resources are not there in your country there is nothing you can do.
Take note that bitcoin total hashrate has increased by around 85% in the past year.
Most of it is on credit.
Compute North went bankrupt, Greenridge sold off $74 mils of equipment, Core Scientific needed life support cash injection to stay afloat, Iris Energy went into debt 100 million to avoid bankruptcy, the spike from 16k to 24k saved half of those companies that have not learned a thing and keep expanding on credit and debt. Popcorn grabbing time!