Sure. There are a large variety of different steroids with different purpose and goals. They are mainly used for body building whether you want to gain muscle or lose fat, but you need to supplement it with proper training and dieting. The most logical steroid and most commonly used one among MMA fighters is testosterone. Average testosterone cycle is 500 mg/per week and lasts 12 weeks. You won't feel a single difference in your mental state for the first 4~6 weeks - it takes time to kick in. Then you will experience higher lust and a bit more confidence but nothing major.
Testosterone, physically, gives you a faster recovery time for your muscles to build. Ever felt sore after a workout? This is the solution and essentially helps you train twice as much as a "normal" person. But playing with hormones is tricky and to avoid getting side-effects (bitch tits, acne, fucking up your endo system) you need to supplement it with an AI, aromatize inhibitor, which, when dosed incorrectly can cause major mood swings, mainly depression and apathy. After a "cycle" fighters also need to pass a post cycle treatment period with different drugs to balance one's endo system. These are what most of the fighters get busted with.
Besides testosterone, turinabol and anavar are steroids of similar effect. But people who think steroids give a massive fighting advantage are absolutely delusional. You feel slightly better, you have a slightly better stamina* and noticeably better recovery time - that it's. There are some stronger steroids like tren with more severe side effects (feeling godlike and getting angry fast) but afaik fighters don't use it, dozing tren and living with sides is absolutely horrible as it's literally invented for breeding cattle for beef and is not approved for human-use. (night sweats, no sleep, paranoia, mood swings)
* debatable as most steroids actually cause more lack of breath.
To sum it up: essentially taking steroids make you feel like a woman, experience mood wings for the trade-off for a higher recovery
source: I'm a steroid user for bodybuilding purposes. I don't even look like I lift but a have the test-levels of a soyboy so training on clean-mode was essentially a complete waste of my time.
edit2: how it ultimately feels: once you try a basic level of test cycle you will never want to go back to normal levels. You feel happier, have more energy, are more horny and confident (depending on steroids, the heavy bodybuilders are absolutely miserable and are absolutely mentally dying)
edit3: steroids are almost a waste of time if you can't afford, time-wise, to train twice the amount you did before. I don't know too many people who can hit the gym 5-6 times per week.
