First of all dont worry about struggling, honestly things will appear, in real life its not gardeners world as we dont have the off camera crew doing all the hard graft!
Over time you will find methods that suit you.
My method for beetroot is to sow in trays and wait for two real leaves then transplant in the ground at the correct distance apart.
This way you dont have to keep messing with thinning them. I sow enough for a row every 2 weeks and I pick them as baby beets for salads. As we hit August a row will be left to grow on for winter as we like Borscht soup.
I dont grow carrot, its too much hard work and I have seen peeps on our site do everything then can and still get hit by the fly.
The biggest tip I can give you is just simply be patient and worry not.