If Joe Biden is serious about a two state solution, he can talk with the veto powers at the UN ( Russia, France, Uk and China ) and ask them not
to oppose any Palestinian's declaration of statehood. In the meantime, he can tell the Palestinian authority in the West Bank to come to the UN and declare that " as of today Palestine is a state , a country ". Once this is done, the SAME DAY, the veto powers sign a declaration recognizing Palestine as an independent country and asking the Israeli troops to vacate their positions in Palestine or face an international military force
the same way the Iraqi troops were kicked out of Kuwait.
Anything else is just hypocrisy because you cannot say the two- state solution is the only one when you back Israel's genocidal campaign in Gaza .