You have different expectations for the game and you need to discuss that.
You must discuss your expectations for the game with the players and reach a consensus or cancel the game and find some other activity. Apart from the very rare professional GM or paid game tests, role playing is a recreational activity and, in general, if it is not fun, it is better to get away than to stay with a game that not everyone enjoys.
That said, this can probably be resolved if you discuss what you want. It seems that you want a somewhat rough game with a tactical emphasis. This is a great game style and quite common in DnD. It's not the only one.
Your players seem to want to play powerful characters in a kind of great joyful adventure situation. This is also a good game style (the one I use most often, personally).
But both are difficult (not impossible) to reconcile. You must talk to your players and find an intermediate point that everyone enjoys or find a different social activity with them. There are several suggested tools that can help you find common ground, including the Tool on the same page.