I use this -

Caldwell Steady Rest NXT Adjustable Ambidextrous Shooting Rest - $25 -

https://www.amazon.com/Caldwell-Adjustable-Ambidextrous-Shotgun-Shooting/dp/B000VZ1IJG/

I only use the front part when shooting. The height of the rest is adjustable by turning the threaded wheel below the rest. Because it is molded plastic, it is a bit light, so to give it some weight I filled a small Zip-Bag with sand and use that to steady it.

Here is just the Front Portion for a bit less money -

Caldwell Handy Rest NXT Adjustable Ambidextrous Rifle Shooting Rest - $20 -

https://www.amazon.com/Caldwell-Adjustable-Ambidextrous-Handgun-Shooting/dp/B001ABQT9E/

And here is a heavier metal version of functionally the same thing -

Caldwell The Rock Jr Adjustable Ambidextrous Rifle Shooting Rest - $40 -

https://www.amazon.com/Caldwell-Adjustable-Ambidextrous-Shooting-Outdoor/dp/B0007Y8SBW/

And there are similar from other brands at similar prices, for example this ALLEN -

https://www.amazon.com/Company-Remington-Shotsaver-Rifles-Pistols/dp/B000W9LAWG/

Though I was not aware that such a product existed until I started searching, here is something that resembles a Screw Jack, that creates an adjustable platform that can be raised and lowered, and upon which you can place your own sandbags.

Lyman Match Shooting Bag & Bag Jack Combo Kit - $75 -

https://www.amazon.com/Lyman-Match-Shooting-Jack-Combo/dp/B06Y319CZN/

I find these adequate for my needs. You have to decide for yourself what specifically meets your needs.

I will say that Sandbags literally filled with Sand are very heavy, dense, and generally hard. I Personally found that Dry Split Pea works better, though most grocery stores have an assortment of dried beans and similar that you might like the feel of better. But what you fill the bags with is a personal choice. I tried sand and didn't like it, so - Split Pea - for me.

For myself, as long as it was cheap and adjustable, I was happy. For yourself, you really need to examine how and how often it will be used, and price your choice accordingly.

So, it really gets down to how far you want to take it. If you want absolute stability, then the Cadwell Lead Sled is very popular and it does allow you to add extra weight if you feel it is necessary. And of course, similar devices are made by other Brands -

https://www.amazon.com/Caldwell-Adjustable-Ambidextrous-Reducing-Shooting/dp/B01MU0N826/

https://www.amazon.com/Caldwell-Adjustable-Ambidextrous-Reducing-Shooting/dp/B01NCLR2L0/

For simply sighting in a Rifle Scope or Red Dot at normal distances, the $20 to $25 plastic Bench Rest are probably fine. If you want to take if farther, get the $40 Metal versions.

Though just me at my range, I find that about 8" to 8.5" of lift for the rifle is about right.

On my other Rifle, because I'm a cheapskate, I have a very basic 6" to 9" Bipod. Priced at about $25.

Example -

https://www.amazon.com/dp/B01E4YVCOA

Again, this is adequate for sighting in at very common 25yds and 50yds, even out to 100 yds.

EDITED: One other point, assuming you are new to shooting, NEVER rest the barrel on the Rest or on the Sandbag. ALWAYS rest to STOCK on the Rest or Bag.