How can I safely install a combination switch/outlet?

Do you know anything about electricity besides it can kill you? What electrical tools do you have and wiring knowledge?

https://www.howtogeek.com/286829/how-to-replace-a-light-switch-with-a-switchoutlet-combo

I hope you have some good DIY electrical skills and knowledge. If not--find someone who does!

Yes you can. Wiring diagram is last picture on the page.

https://www.do-it-yourself-help.com/light-switch-wiring-diagrams.html

My suggestion is to purchase what is called a grounded tap switch. Simply plug it into an existing electrical outlet that is already installed in the wall. There is no 'electrical' work necessary. When it is plugged in, the other side of the outlet is still free for something else. If you do need that side for something else, instead of the lamp, then simply unplug it.

The first picture below shows GE brand, the other two are Leviton.

If you are wanting access to a lamp to turn it on and off and it is not convenient to either reach up under the shade, or to crawl down to where the tap switch is plugged into the wall, an option is to purchase what is called a table top or credenza dimmer switch, which also turns on/off. Simply plug it in, like an extension cord; no 'electrical' work necessary.

The pictures below show Lutron brand.

We turn off our lamps with a remote. You put a receiver in your plug in. Then plug your lamp into the receiver. A remote turns it off and on. Check with big box stores. Amazon has them also.