In my WIP, my progress has stalled because I just have way too many ideas flowing in my head. i know the main points I want to hit, but I just so many ideas on how my character gets there that its become to to point where I can't anymore because I always end up changing what I have. Any suggestions on how to channel all those ideas into something useful/productive so i can get back to writing?
You might just have to write several versions, each one with different ideas, and decide which you like best. Usually, I can only tell whether my ideas are actually good when I write them into a story. The act of writing makes me think deeply about the ideas, more deeply than I do just sitting around and musing, and often I find that what seemed to be a good idea on the surface turns out to be unworkable.
I change mine all the time - I have so many ideas lol I have twenty years worth of story in my head. I produce tales as fast as I can type. Can you meditate? I used relaxation breathing to calm my brain down. Because I have dyspraxia which produces similar brain patterns to ADD/ADHD my brain works in circles rather than a linear fashion it whirls around spewing out so many ideas. I just now accept it.
Store your ideas for future use. The ones you don't use now, you can use in a different story or even a subplot for the same one. If the character has an awesome way to solve a problem, but you're going with a different method, save the first one for the next obstacle the MC encounters.
Like minstrel said, writing them all down is probably the best way to flesh out ones you like better than others. Another perk to writing them all down is that you can file them away somewhere for future reference, like Mallory said.
I've got a mountain of notepads, all filled with ideas. Just get them into a permanent state - anything from characters, to quotes, and curious events. You'll have a bank to draw of ideas to draw from.
Give them time. A lot of ideas seem bubbly at the moment of conception, but over time they'll settle. Some float, some sink.
Why not just keep writing? Your characters will choose a path, and then eventually get to their destination. A story isn't "the characters do ALL OF THIS AT ONCE," but "the characters did this, then this, then that" and so on. Stopping because of too many ideas is sad. There will be other stories, other opportunities to use those other neat ideas. But for now, why not just focus on getting the story -- and just one version of the story -- down on paper?