How to buy windows and an office through public procurement?

Question

Auction

The crux of the matter: I don't want to sit on conditional Astralinux and "my office", with all these laws on import substitution, I would like to somehow drag Microsoft products. The institution is absolutely new, so the excuse about "Expanding old licenses" does not work. The excuse about "buy computers with pre-installed software" is rejected by the accounting department, they say, these are different budget items and you can't buy a kit.
Has anyone been shopping lately? share your experience