all the world should stay at home this time cause of COVID-19 i got that, but what about the 150 million homeless around the world?!?

They can stay at "their homes", whether it is under a bridge or where ever those people go when they are homeless.

They are quite likely to get sick and a lot of them are more liable to die,.

they are on their own sadly

They also can stay at home which is outside, right where they are 

Accept for essential workers, other workers should be at home. The homeless usually don't have jobs, but they should at least be socially distancing them selves from other people. 

The only hope is that God will intervene in human affairs and solve the problem of homelessness and other problems. The Bible promises: «They will build houses and live in them, and they will plant vineyards and eat their fruitage. They will not build for someone else to inhabit, nor will they plant for others to eat. For the days of my people will be like the days of a tree, and the work of their hands my chosen ones will enjoy to the full» (Isa 65:21, 22).
“No resident will say: ‘I am sick.’ The people dwelling in the land will be pardoned for their error.” (Isa. 33:24) 

Sure. You go ahead and stay home and starve. But if and when the homeless bring you food, tip them well.

Invite them in to live with you.