Lots of advice,not going through it all.
But
1. Determine your TDEE here
IF Calculator
2. Diet-Carbs(fruits,beans,natural stuff)
Protein(Chicken breast,steaks,fish,least processed stuff)dairy ,eggs
fats(olive oils,coconuts,natural butter,nuts)
3. Supplementst Fish oil as EFA are just that,essential. Vitamins as well as kelp for iodine. I would throw in a b complex as wel, I use garden of lifes for all mine.
stay away from processed salt and sugar,
really
4. Exercises-Compounds such as sqauts,deadlifts,bench presses,shoulder press ,rows,
Can you do a pull up? If not,use the machine that assist you at the gym if avail.
Isolations-Triceps extensions,bicep curls,and ham curls.
The compounds will get your iso showing more than anything.
As for but,lunges are great. Hip thrust can be thrown in,but from experience,lunges and wide stance squats work best.
Total volume-small groups(biceps,shoulders)30-60 reps a week,split into 2-3 workouts.
Big groups(legs,chest) 60-120.
As a beginner,you will benefit greatly from full body workouts,3-4 days a week.
Mon,Wed,Fri,Sun,Tue,Thur,Sat. Rest one day in between .
Diet and sleep will determine your success more than anything.
No need for supps like protein or anything else yet. Let your body receive those noob gains.
As far as the squatting,dont have to go heavy.
Say you start with body weight,
Do 2 sets of 15 each workout,then just add 5 pounds each week(not time)
Low weight-higher reps
High weight-low reps. As long as volume is met(total weight lifted,example 135x10x4 sets)
Good Luck.