Train reservations—how to reserve forward facing seats

For Eurostar, the website gives a seating map that shows which direction the train is going in. I've also gone to https://www.seat61.com/ - it's a great website for picking out the Eurostar seats, and there's a lot of information for other trains too.

I used that site on my first trip on the Eurostar, I have the same problem with not being able to sit backwards. I actually got my husband and I seats at one of the tables so we'd be across from each other, in case I messed up and picked a seat facing the wrong way, lol.

I don't use apps, but on the LNER website which I have open now, you will be automatically offered a seat- then below that choose 'Manage your seat reservation', you will then get a train plan which at top right shows you the direction of travel. Then choose which car you wish to travel in, then your seat (which should go green), then hit the 'Save your changes' button.
I imagine the app does the same thing.

If I book an LNER (or any other train) on Northern it asks me to choose forward or back, aisle or window, power socket or not, table or not and quiet car or not. Based on those preferences the system then allocates me a relevant seat.

LNER should do the same for other operators- for instance GWR.

Bear in mind a train can end up 'in reverse formation' for various reasons (that is, basically travelling backwards) in which case it all counts for nothing. Your forward seat will then be backwards.

Assuming you aren't traveling solo, if the carriage is equipped with facing seats, you can reserve a pair or more facing one another, and then switch off if necessary.

Also note that some trains have the seats aligned with windows whilst on others, pillars between the windows obstruct the view. I tend not to reserve a seat but just board and look for a vacant seat that is forward facing and with view not obstructed. I also sit on the shady side of the train if possible on sunny days. Some trains don’t have reservations in any case - certainly local ones. However, it it prudent to reserve a seat if the train is going to be busy.

The LNER app works the same way as the website.

After you choose your train, you'll see under "reservations" that you have been assigned a seat. If you don't like it, click on "view/change" and a seating chart will show up. You can then choose a new seat. On the side of the train diagram it will point out the direction of travel. You can choose your seat prior to purchase.

You can also choose your seat on Eurostar but after purchase.

The Seat 61 explains it all.