My lack of confidence makes me feel unattractive and lonely

I feel really unattractive.

I know I'm not exactly physically attractive, I don't like it but I can deal with that.

My issue is I'm so unconfident. I think my shyness and utter awkwardness is really unattractive.

And I know that feeling unattractive makes me less confident thereby making me less attractive and I goes in a cycle of not feeling very good about myself.

Sometimes I feel great about myself. Sometimes I chat with a girl or something and maybe I feel better. Sometimes I just feel more confident and better about myself.

But so much of the time I don't feel confident in myself, I feel quite insecure.

I think I'm a nice person (I hope so), I always try to be polite (help people out with things, saying hi to strangers, hold doors for people, always smiling, etc, yknow normal stuff) and I think I've got a fun personality, I've relatively funny, I think.

I'm clean. I shower every day. I clean my teeth twice a day for 2 minutes. I always wear deodorant. I do all those normal things that every clean person does.

My other issue is that I'm not very fit. I don't go the gym or do much exercise (though i do go walking a lot), so I'm a bit overweight. I want to start going to the gym, I'm just scared to, its confidence again. My friends often invite me though I just need to go with them soon.

I don't blame anyone else for me being single (obviously) but I want to figure out how to improve myself and feel less unattractive, as I know my feeling shy, awkward and unconfident, both about my appearance and about other things, is what's holding me back.

If anyone can give any advice, that'd be great, thanks 😊