I download Bitcoin Wallet app. I receive BTC on first address (old type), but after some time second address (bech-32) became "this is you current address for receiving". Can I change receiving on first address?
The wallet generates a new receiving address every time you touch the "Request coins" button at bottom left. This is normal and is done for privacy reasons. The last one in the list is labelled "This is your current address for receiving" but you can re-use earlier ones if you don't care about privacy or if you really know what you are doing (e.g. receiving regularly recurring payments from same person).
There is no need to do anything with old addresses. They can be reused if you really need to but there is no harm in leaving them alone.
If you want to generate new old-style addresses for receiving payment from someone with old software, I don't see any way to do that with the current version 8.08 settings menu. It always generates new-style Bech32 addresses with a bc1 prefix so far as I can see.