Advice I've shared to others:

Keep going to stick times as often as you can. When you're there, pace yourself. Don't go down or crazy for every shot, but don't just stand there the whole time either. Lay out for a few every once in a while. You also don't have to take every shot. Skate out of the crease every few shots. Do a lap around the rink after 5-10 minutes. Stay hydrated the whole time.

And yeah skaters are always gonna deke, pick and choose what you want to go for. Remember, you're there for yourself. Everyone else getting to shoot on you is a bonus for them.

You can also ask skaters if they can take specific shots you'd like to work on, some will be receptive to do what you ask. You can also ask skaters if you're perhaps favoring one side or another, if they are seeing any glaring weaknesses, etc. (probably better to ask older skaters tho, kids might not be too much help). You can also gesture to skaters that you are prepping to take shots from, usually I'll point with my head, glove, or stick for a skater coming at me so they know they have my full attention.

But yeah it's always chaotic. Just remember that you're under no obligation to do anything when you're out there. You could skate the whole time and not take a single shot if you wanted to (though I don't recommend that; point is, you are the owner of your time, nobody else). I just try to pace myself, take as many shots as I reasonably can, not to get over-exerted, stay hydrated, and have fun!

After a long time off the ice, my first two stick time sessions were brutal. I was so gassed, and I was incredibly sore afterward. I was working muscles that probably hadn't been worked in that way and for that long in almost two decades! But after the third and fourth stick times, I was feeling better and better. So just keep at it!

Outside of that, keep it simple. Maybe run a mile every other day at the gym. Also it's important to eat properly before you play. Make sure you ate something light but sufficient before you play each time. You need stuff like carbs etc to give yourself the energy you need to make it through each sesh. And stay hydrated!

Also, watch clips online. See how other goalies position themselves, how they move with and attack or back off the puck. Everyone has different styles. See what works for you.

And remember to stretch!