Yes all the brothers from the previous marriage and the second wife along with her daughter are equal shareholders in such property. However since this is an ancestral property you can sue for partition against your step mother.
If parties are unwilling, then such disputes cannot be settled out of court. unless off course you find a third party buyer you would be interested to buy your undivided share of such property at a decent price. In case of such sale do ensure to make pre-emptive offers to your other relatives as otherwise such sale will be invalid.