MacBook Air or Pro?

Base model four-port 2020 13" MacBook Pro. If that's too pricey, then go for a two-port 2020 13" MacBook Pro and make sure you spec it out with at least 16GB of RAM. Do NOT go for the 2020 MacBook Air. Many are having thermal issues with it due to the CPU being passively cooled and the fan not being connected with that cooling (hence the passive cooling).

The four-port model will last you longer and have greater performance, but it does cost more. The two-port model is still using low-end 8th generation Intel Core processors, while the four-port is using mid-range 10th generation Intel Core processors. While this may not determine when your Mac is left out of a future macOS release, there are many videos on YouTube that go into detail as to the performance and thermal differences between these two Mac models.

I strongly recommend avoiding the 2 port Pro. The upgraded Air is a far superior device to the 2 port MacBook Pro. I have issued the 2018+ Air to over 100 staff and had zero issues.

The 2 port Pro still outperforms the Air in benchmarks. The upgraded Air still has insufficient passive cooling making. Honestly, I'm only throwing the two-port Pro out there because the OP has a budget constraint. Otherwise, a 4-port 13" Pro would be my bare minimum consideration if one is to be buying an Intel based MacBook Pro.

Respectfully, that's an inaccurate assessment. The MacBook Air is NOT more closely resembling the iPad than most macOS devices. It resembles more closely the 13" MacBook Pro, but with a less powerful CPU. The less powerful CPU is not a problem for many uses, I'll agree, but not most. There are many YouTube videos and customer reviews as well as professional reviews that state otherwise. The Air uses passive cooling and not enough of it. A dual-core i3 will choke on a game of the stock Chess app, for instance. If you are getting an Air, a quad-core processor is a must. I'd even go i7 over i5. But even then, the passive cooling on the processor is a problem, so much so that there's a whole sub-community dedicated to fixing it with third party modifications.

There is nothing wrong with the Air. It is a different style of hardware design more closely resembling the iPad than most macOS devices. This style works fine for most uses (even photoshop).

The MacBook Air upgraded to the i5 processor is a better device (and cheaper) than the MacBook Pro at the closest price point. The current i5 in the MacBook Air is a 5th generation quad core while the current i5 in the low end MacBook Pro is an 8th gen quad core.

Given that the transition away from Intel Macs and to Macs with Apple Silicon systems on a chip (SoCs) as well as recent rumors about which Macs are likely to make the jump at which times, it seems as though Apple is likely not going to make another Intel based MacBook Air after this one. Similarly, they may not resolve the issues with this one before they put out a MacBook Air and/or 13" MacBook Pro that uses the new Apple Silicon processors. Given the Apple Silicon architecture, I would imagine that the current thermal setup of the current MacBook Air would be fine for those processors (and that assumes that they'd be using the same exact design). Then again, Apple may want to push the levels of performance of those chips to the point of needing better cooling (in which case they may give it better cooling). What they do isn't yet known for sure outside of Cupertino. But it's probably safe to assume that the current MacBook Air is the last one with Intel processors, in which case any changes that you want will have to wait until we're on the other side of the Apple Silicon transition with that Mac.