A short-term bridge loan is the usual tool when the dates cannot line up exactly, letting you access your current home's equity before its sale actually closes so you can complete the purchase without a gap in between.
The other common tool is a rent-back, where you sell your home but negotiate to stay in it as a tenant for a short period after possession, buying yourself time to move directly into the new place instead of into temporary housing.
Which tool fits depends on how close your two closing dates can realistically get and how much timing risk you are comfortable carrying. Get your hand-reviewed valuation from Joel Dyck.