His unwavering support for Israel during their campaign of atrocities is despicable and shameful.
If we're going to get Trump again it's in part because of the absolutely all-or-nothing brook-no-compromise attitude of voters. Like this, for example. Biden's support has not been unwavering, he's criticized Israel's actions. But not enough for you, and so he gets no credit whatsoever for any moderation he might have. And that's why you say he "feels like a Republican" to you, because someone can only be 100% totally on your side or they must be on the other side.
I'd love for there to be a viable fully-progressive candidate who happened to agree with everything I believe in. I'd also love to have a pet unicorn. When elections actually roll around in reality, though, none of the candidates are going to be perfect. And unfortunately in many first-past-the-post electorates the system is set up in such a way that there are only two viable candidates. So pick the one that's closest to your views. Push for better candidates in the primary, of course, but accept that you won't always get everything you want.