Start going for a walk every day, for at least 30 minutes.
Exercise. Exercise every day. Exercise is great for feeling good. Even something simple, just get up and start moving.
Cold baths/showers. Start with a short amount of time at first, maybe a minute or two. It does you a power of good, mentally. Helps the parasympathetic nervous system and the vagus nerve, which make you calm and think more clearly. It might feel uncomfortable when you first get in, but you emerge feeling glorious.
Breathing exercises. I would recommend the 4-7-8 breathing exercise, breathe in for four seconds, hold for seven seconds, and exhale for eight seconds. Do that about 8 times. Another good one is Andrew Huberman's physiological sigh, inhaling deeply twice, then exhaling once for a longer amount of time than you inhaled. Do that about 10 times.
If you watch porn and/or jerk off, stop. Stop watching porn and stop jerking off. Retain your seed. Only release your seed when you find a girl you can marry and make babies with. It might be difficult to retain at first, but when you start to get the hang of it, you'll feel the rewards. Transmute that energy through exercise. Get outside more. Make art, if not, maybe that would be a good hobby. Instead of looking at porn, use that energy to create art. Before porn ruined society and made depictions of nudity oversexualised, artists would transmute their energy and create nude art.
If you're religious, pray everyday and trust in the Lord. If you're not, consider getting closer to God. I'm a Christian and I've found that going for a walk and praying does wonders for my mental health. Find a quiet place where you can pray in nature. I've found also that taking some time before I go to bed to do breathing exercises and pray does wonders for making me feel chill and peaceful.
These things will help you a great deal, mentally. Get yourself in a good place mentally and stand up to the people who are abusing you in life and in the workplace. You are unstoppable.
God is looking out for you, even if it doesn't feel like it sometimes. There are times where he has to pick you up and carry you. With Jesus Christ, you can do anything.
It's ok, my dude. Cry if you need to cry. But remember that God is with you and he's looking out for you. It's all going to be ok. You've got this.
4-7-8 breathing exercise:https://www.youtube.com/watch?v=BmyL7ItzfaE
Physiological sigh:https://www.youtube.com/watch?v=rVnChXmzf08