Smelt cobblestone in a furnace to get stone
Place stone in the crafting table with no spaces between blocks to get stone bricks
Crafting recipe: 2×2 stone blocks in the crafting grid
Alternative: smelt stones to get stone, then craft stone bricks from stone blocks
Alternative: use a blast furnace to smelt cobblestone faster (then craft from stone)
In Bedrock/Java, stone bricks can also be obtained by smelting stone in a furnace in some versions/mods where applicable