Hi @jac74 ,
It’s not that hard but you need to have smd (surface mounted device) soldering skills and tools to do the repair.
It is not a job for novices, but if you decide to try it, practice on some old faulty boards first before working on the phone.
Here’s a link to a video that shows how to remove / replace the charging port on the phone.
Here’s a link to the ifixit LG K20 Plus Repair guides that may help as well.
Replacement connectors are available online. Just search for LG K20 Plus USB charge port to get results for suppliers of the part.
If this seems all too daunting, contact a reputable, professional mobile phone repair service and ask for a quote to repair the charge port. No doubt it will be cheaper than a new phone in the long term