To answer the question directly:
https://joebiden.com/immigration/
Ballotpedia's summary:
Joe Biden's campaign website says he will adopt the following border security policies: "Surge asylum officers to efficiently review the cases of recent border crossers and keep cases with positive credible-fear findings with the Asylum Division. Address the root causes of migration by fostering greater security, economic development, and respect for the rule of law in Central America. Invest in better technology coupled with privacy protections at the border, both at and between ports of entry, including cameras, sensors, large-scale x-ray machines, and fixed towers. Improve cross-agency collaboration. Work with Mexico and Canada as partners — not as adversaries."
That begs another question: What is a larger source of poverty, drugs, and gangs - domestic citizens or the southern border?
Poverty from 2018 Census Data
Approximately 12% of the US population (38.1 million) falls into the poverty definition. The poverty rate for native born people is 11.4% (31.8m); foreign-born citizens, 9.9% (2.2m); and foreign-born non-citizens, 17.5% (4.1m). Roughly 80% of people in poverty are native born.
Drugs
Marijuana is legal in many states. The most recent epidemic of drug abuse was created by legal US & multi-national pharma companies. It decimated more than a few rural, white areas.
Gangs
I am not sure. It has been said many people fleeing to the US are trying to escape gang violence in their home countries.
The border issue is important and should not be ignored. However, we have our own home-grown issues which need addressed.