As the others have mentioned, it's clipboard jacking malware that is the danger there and can be mitigated by simply confirming the address with your Mark.I eyeballs at least once and maybe twice before clicking "send" or confirm etc
Trust Wallet supports BIP39 as far as I know, so you should be able to create your wallet and get the 12 word recovery phrase. Make a note of your receive address, then delete the wallet... and then restore it from your recovery phrase and make sure the receive address matches the original. That'll confirm your wallet and recovery process are working BEFORE you really need it!
As for testing it... the only way to really do it with Trust Wallet is to send a small amount... start with sometime small if possible, although be aware that if you attempt to do this when fees are high, you could end up losing a significant amount to the fee. Do you have any friends with Bitcoin that might be willing to assist by sending you $5 worth of Bitcoin that you can then pay them for or send back to test?