Agree with @Ch3rish there are already a ton of threads on this subject.
Just say you don't taken packages in (to anyone trying to leave one with you for a neighbour.)
We do. I HATE taking packages in for people, as it's a burden. You have to keep it in your home, you have to have responsibility for it, and you have to wait for the neighbour to come and get it. (Or sit there/stand there and wait for said neighbour to come in, so you can take it over, in the dark and the cold and the rain, and hope they hear you knocking on the door!)
I NEVER take packages in. And before anyone asks, NO, I don't expect people to take them in for me. I have a designated safe space for my packages, where the postie or courier can leave it.
We got a package last summer, for a 'cheeky fucker' neighbour who moved in (kind of opposite us,) a few weeks before. The courier knocked their door and they didn't answer. (Weren't up even though it was midday.)
The courier caught my DH off guard, as he was in the garden weeding the flowerbeds. He said 'the neighbour at No. 10 has given you as a drop off point if they're not in, or they don't answer the door.' Annoyingly DH took it and brought it in. A huge package around two thirds the size of a fridge! 
What a cheek! They had barely said a word to us (or any other neighbour) in the 5-6 weeks they'd lived there, and yet they had named us (at number 7,) as a drop off point for their packages, if they weren't in (or didn't hear the door go, or were in bed!!!)
That was the first and last time those neighbours did this. We saw another courier (a few days later,) knocking on their door and getting no answer. He walked over to our house, and knocked our door, and we opened the window and said 'we don't take in packages for anyone, and especially not in the current climate - with covid19. Also, they are IN, so just keep knocking until they answer. They must know you're coming!'
I mean what kind of person expects others to take their shit in, just because they can't be fucked to get their arse out of their bed?! As I said, especially in the current climate. I'm not taking someone else's package that's been handled by a dozen people, and will have to be taken around to someone else's house. (And it will, because the neighbour never came for the last one, DH went over to take it!)