Can VA homeloans be used to buy land and have a house built on it?

Bottom line. Yes you can. But it’s a long and tortuous process and all expected costs need to be verified thrice over from builder and then banks appraiser.
The guidance has been changing a lot so your best bet is to get a mortgage specialist well versed in VA loans and they’ll square you away. Good luck
Again it’s not impossible but it’s much easier to just buy a new construction.

yes you can, kind of. i am currently building a house. you need to get a normal construction loan during the build process. and then close to the completion date, you refinance(might not be the right term) into a VA loan. there is tons of paper work, i think i sent the bank over 100 pieces of paper. and there are a lot of inspections and appraisals. But it is a good process. it saved me from making a $50,000 mistake when the house we originally wanted to buy did not appraise for what they were asking. VA would not back the loan and the builder refused to even negotiate about a lower price. so we walked away free and clear because of the VA loan clause that should be in every contract.

I've asked this one a million times over 20 years or more, and no on seems to have a direct answer.