Most of this is a mood lmao. Even though I was literally born in latinamerica and lived there until 2nd grade, I can no longer stand such hot weather. I hate it. I hate feeling hot, I hate feeling sweaty, the sun hurts my eyes, and argh I hate that there's nothing you can do about it except cope and wait until autumn because what are you gonna do? Walk around naked?!. No thanks. I also much prefer wearing jumpers and coats and feeling cozy which you can't do in summer.
Something that's helped me with the clothing aspect is buying some cute summer clothes and coming up with outfits that I actually like that I can wear when it's hot. Idk if you're a guy, gal or pal, but I like wearing crop tops with short sleeved button up shirts over to give the illusion of layering without actually adding any extra warmth.
With the bo thing, there's not much that you can do except make sure you shower everyday and put on some good deodorant. Maybe carry deodorant around with you and reapply when you think you need it. Also maybe find a perfume/cologne you like to wear as well? That might help make you feel less conscious about it.
And I can totally relate with the anxiety around nice weather meaning that you have to be in a good mood. Sometimes I dissociate when I'm outside and it's sunny (probably to do with my sensory overload issues tbh) which makes me feel weirdly numb and extremely out of place.
About your last point... idrk what to tell you. Ig it is normal to find other people attractive and want to look at them, but there is a line you have to not cross. Maybe try to distract yourself with your phone or something.