I don't know about other pharmacies but Oushk send a pretty detailed booklet that cover everything you need to know about the injections - when/where/how etc. It explains all side effects and gives advice on dealing with them.
You can work out how many calories you need by finding out your TDEE (total daily energy expenditure) and subtracting 500. Eg. if your TDEE is 2000 then you can eat 1500 calories a day to lose 1lb a week. BMR is basal metabolic rate and that is how many calories your body needs just to function and keep you alive. It's not recommended to eat below your BMR.
Not eating enough calories might lead to faster weight loss but will cause fatigue, muscle loss, hair loss, nutrient deficiencies, gallstones etc. Nourish yourself appropriately and focus on learning long term sustainable habits.
30g of fibre a day is recommended for every body. I feel better when I have a bit more so I take a supplement (biomel).
You can track your calories and nutrients on apps like nutracheck (the best), myfitnesspal, fitbit etc.
I like using a fitbit to track my exercise. I aim for 12k steps a day which "earns" me an extra 400 calories a day.
Resistance/strength training is recommended because on WLIs muscle loss can account for up to 40% of total weight loss. That's why consuming enough protein and not calorie restricting too much is so important. You will end up weak and "skinny fat".
I follow youtube tutorials for dumbbell and body weight exercises I can do at home. There are lots to choose from, just find some that work for you.
Do exercise that you enjoy, that's the most important thing in my opinion because you'll be able to keep it up!
Drinking enough water is vital! I drink 4-6 litres of water a day. On days where I only drink 2-3 I find I'm quite bloated and usually the scales will show a gain because of water retention. It can be hard to do but I feel it's made the biggest difference to my body.
There is lots of info and help out there regarding WLIs! It can feel daunting at first but once you do it you'll find it's actually easy enough. There's lots of support groups too - here, reddit, fb, nutracheck forums etc.