Lots of alternatives to rice, pasta and potatoes available:
cauliflower can be riced, mashed, steamed, roasted
Swede, celeriac and turnip are all much lower carb than potato, sweet potato, parsnip and carrot (but individual tolerances vary hugely so check what your bg does for each)
Some people tolerate buckwheat (incl soba noodles) better than they tolerate wheat noodles
There are numerous low carb breads, either bought cooked, bought to bake yourself, or starting from scratch with a recipe
you can also just have more veg, and then add butter, olive oil, grated cheese, low carb cheese sauce (yum!)
I always took the view that bread and pasta were just their as a vehicle for the sauce and filling, so found it relatively easy to subtract the stodge and enjoy the sauce/filling undiluted.
look up ‘fathead pizza recipe’ and ‘fathead pastry recipes’
Also ‘keto cake recipe’ ‘keto brownie/cookie/muffin/crumble/choc mousse/whatever floats your boat’
Also have a look for something called ‘bulletproof coffee’ or ‘bulletproof hot chocolate’, or ‘keto golden milk’