How do I

guys, i am making game. but i dont know how to make it like. I hav 5 missions. all must be locked. after finishing first mission, the next one must be open. and after finishing 2d the 3d mst be open like. mission ends. move to mission select room and there is 5 missions with the next unlockd. hope u understand what i mean. like most popular games angry birds, croco, and etc. hope u help me.

You need to use local storage to keep an variable value which shows which stages are beaten, lets say on start its set 0, when player reaches the finish line on level 1 add + 1 to the variable only once, next you will need an event that checks the value of the variable if its 1 unlock stage 2, if its 2 unlock stage 3 etc.

When the player exits the game, you will have to keep the variable in local storage so when he comes back he can continue from where he left before exiting the game.

thank you! and how i can make mission finished? for example when my enemies dies??

That depends on how you like to design the level, you can have like an exit sprite so when the player touches it the level is complete and you increment the variable, or you can track the enemies and when all are dead you make the level complete.