Buying clothes and shoes in the store can be quite scary initially, but it gets easier with time.
Try taking small steps to get used to it. Start with department stores (talking to a sales person can be way scarier

).
After you get a bit more confident, take something to the dressing rooms.
Mayebe do that somewhere you usually don't go, so you can think "I'll never meet anyone here elsewhere, so who cares", which is a bit reassuring.
Next try doing the same in a boutique store. Maybe buy something saying it's a gift (they probably will know it's not, buy will go along).
Then try clothes on in the boutique. Maybe ask a sales person for another size or color.
Somewhere along that path you will get the courage (or stop caring for what others think) to try shoes in the middle of the store

I'm still in the closet so I always shop in drab.
When I first started buying things in person I was very scared, walking around in circles many times trying to buildup courage to pickup something and get out as fast as I could.
Now I put on heels and walk in the store, take clothes to the dressing rooms, ask clerks for sizes / styles / whatever ...
I still get a bit nervous, but not nearly as much and now think it actually adds to the fun of shopping