Surf at home using the IP address at work?

I would like to use my laptop at home (Internet Vodafone) to surf via the IP address of my business computer (Telekom Internet). What options are there?

Google on the subject of VPN. Does your employer offer something like this?

No. This is my office, so to speak. I would have to build a system for myself.

Good IT at the employer will not allow that. In contrast, the connection to the company network should only run via (company) VPN.

Even better company IT (like mine) only allows company-owned hardware anyway, everything else can open the gate for malware into the company network!

Does your business computer have the ability to install third-party software? So company-controlled or free

With the latter it would be possible via VPN

Have you ever heard of VPN? Plus, a responsible employer wouldn't give you administrator rights.