It seems to be a fungal infection in your left armpit. I suggest you see a dermatologist to look into the rash, and get a medication accordingly. Deodorant should also be avoided as it might make the situation worse.
 

Sweating is your body's natural way to cool down. Certain medications can increase sweat production as a side effect or be symptoms of underlying medical conditions. Anti-sweat tablets reduce sweat secretion but may interact with your current medications. It's crucial to consult your doctor for a safe solution. They can adjust your medications or suggest alternative treatments to address the root cause of your sweating. Always communicate openly with your doctor about any concerns or changes in your medication regimen to ensure your health is prioritized.

"skinny fat" in your tummy, thighs, and butt is quite common. "skinny fat" refers to having a higher percentage of body fat and lower muscle mass, even if you appear slender. This can be due to factors like a lack of exercise, poor diet, or genetics. To address this, incorporating strength training exercises, such as squats or lunges, can help build muscle and tone those areas. Also, focusing on a balanced diet with plenty of protein and veggies can support your fitness goals.

Blackheads are small bumps that form when hair follicles get blocked by dead skin cells and excess oil. This can happen due to excess sebum, hormonal changes, or improper skin care. To reduce blackheads, use a gentle exfoliating scrub and a non-comedogenic moisturizer. Always clean your skin well to avoid irritation and prevent the urge to squeeze blackheads.