You need to eat lots of food. Lots and lots of food. Whey is good after you lift. I wouldn’t use anything more than that. Most whey protein powders have all the nutrients you need after you lift.
Are you getting stuck at a body weight or stuck at a weight in exercise weight?
For body weight, I would recommend the first paragraph. and to read up on this link. It helped me out.
If you are stuck at a weight for lifting, try to substitute some exercises for others. Or do an alternate workout for a couple days( maybe like a p90x type thing or a deck of cards). Mix up the workouts you currently have, if you do legs first, do them second vice versa.
Make sure when you increase weight when you workout you go up 10 lbs for legs(5lbs each side for a bar), and 5lbs for upper body(2.5lbs each side).
Focus on doing perfect reps with lower weight, change the number of reps you do. there’s a million things you can do.
The key is do something different, your muscles are used to your routine, you need to ‘surprise’ them with something different.
Here’s a link to a website that can show you lift information, so you can substitute some lifts for others, or develop an alternate workout.
Someone else can chime in. That’s just my two cents on the matter.
Good Luck! I’ve been where you’re at before, you just got to keep plugging along.