Pickup from courier store

I have two shipping methods. Delivery at home and pickup from courier store. Based on our business requirements if the order is above 50euros I have free shipping for both shipping methods. If it is below I have a shipping charge.
What I want to be able is when the user selects pickup from courier store to be able to show a dropdown with all the stores of the courier and the user select which one he  wants to pickup its order from. How can I achieve this?

Thanks in advance

Have you considered "Pickup in store"?  (shippingsettings.allowpickupinstore)
You can list multiple pickup points in the Pickup in store configuration.

Note that when pickup in store is enabled, the "Ship to the same address" must be unselected by the customer at the top of the billing address page (assuming you've enabled it with shippingsettings.shiptosameaddress), otherwise if left selected, pickup points will not appear.

But as I mentioned I am charging based on order total. With pickup points there is not any way to do that apart from a fix fee.

RE:  "But as I mentioned I am charging based on order total. ..."

Actually, you said "if the order is above 50euros I have free shipping for both shipping methods. If it is below I have a shipping charge."

You did not mention that the fee is based on the order total amount.

The former is handled if you set "Free shipping over X"  (as the pickup fee is considered like a shipping charge).

For the latter, "fee is based on the order total amount", please describe that.  (E.g. is it a percentage of the total?  or, based on ranges?)

Based on the order total. I don't think Free shipping over X works because I have to set shipment methods as the user might want to choose between these methods.

This are the settings I have

https://ibb.co/HnRhLch

Your configuration shows only ranges set for method "Delivery at your door".    Unless you have the setting at the bottom of that screen selected "Limit shipping methods to configured ones", you will always get one record for method "Pickup from courier store".    If you need to show the customer multiple pickup points and/or different fees for different order amount ranges, then you need to add more records/ranges.

(Note, however, that when you use Shipping Methods, rather than "Pickup Points", the customer will have to enter a shipping address, or select "Ship to the same address" on the billing address page).

But I have to add one shipping method for each pickup point. I have more than 50 pickup points.
Lets say I do it how are they then displayed into the checkout mode? Are they being shown as dropdown?

It will depend on if you have a custom theme or not;  out of the box, shipping methods show as radio buttons (in the one page checkout, there are three columns).  You could modify a .cshtml file to change that if you know HTML.