Cannot install drivers for Wireless USB Adapter Realtek 8811cu

I have recently bought this Wifi adapter: https://amzn.to/3cUBvjd.

I run Ubuntu 20.04.2 LTS and the info about my kernel is :5.4.0-66-generic #74-Ubuntu SMP Wed Jan 27 22:54:38 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

I have already tried a lot of things while following many posts about this topic. In first place, the adapter comes with a disk. When I execute the install.sh, it doesn't work.

#make -C /lib/modules/5.4.0-66-generic/build M=/home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212 clean
cd hal ; rm -fr ///.mod.c ///.mod ///.o ///..cmd ///.ko
cd hal ; rm -fr //.mod.c //.mod //.o //..cmd //*.ko
cd hal ; rm -fr /.mod.c /.mod /.o /..cmd /.ko
cd hal ; rm -fr *.mod.c *.mod .o ..cmd *.ko
cd core/efuse ; rm -fr *.mod.c *.mod .o ..cmd *.ko
cd core ; rm -fr *.mod.c *.mod .o ..cmd *.ko
cd os_dep/linux ; rm -fr *.mod.c *.mod .o ..cmd *.ko
cd os_dep ; rm -fr *.mod.c *.mod .o ..cmd *.ko
cd platform ; rm -fr *.mod.c *.mod .o ..cmd *.ko
rm -fr Module.symvers ; rm -fr Module.markers ; rm -fr modules.order
rm -fr *.mod.c *.mod .o ..cmd *.ko *~
rm -fr .tmp_versions
Authentication requested [root] for make driver:
make ARCH=x86_64 CROSS_COMPILE= -C /lib/modules/5.4.0-66-generic/build M=/home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212 modules
make[1]: se entra en el directorio '/usr/src/linux-headers-5.4.0-66-generic'
CC [M] /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/core/rtw_cmd.o
In file included from /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/osdep_service.h:47,
from /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/drv_types.h:32,
from /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/core/rtw_cmd.c:22:
/home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/osdep_service_linux.h: In function ‘_init_timer’:
/home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/osdep_service_linux.h:295:8: error: ‘_timer’ {aka ‘struct timer_list’} has no member named ‘data’
295 | ptimer->data = (unsigned long)cntx;
| ^~
/home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/osdep_service_linux.h:296:2: error: implicit declaration of function ‘init_timer’; did you mean ‘_init_timer’? [-Werror=implicit-function-declaration]
296 | init_timer(ptimer);
| ^~~~~~~~~~
| _init_timer
In file included from /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/drv_types.h:35,
from /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/core/rtw_cmd.c:22:
/home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/wifi.h: At top level:
/home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/wifi.h:1019: warning: "IEEE80211_MAX_AMPDU_BUF" redefined
1019 | #define IEEE80211_MAX_AMPDU_BUF 0x40
|
In file included from /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/osdep_service_linux.h:86,
from /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/osdep_service.h:47,
from /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/include/drv_types.h:32,
from /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/core/rtw_cmd.c:22:
./include/linux/ieee80211.h:1460: note: this is the location of the previous definition
1460 | #define IEEE80211_MAX_AMPDU_BUF 0x100
|
cc1: some warnings being treated as errors
make[2]: *** [scripts/Makefile.build:271: /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212/core/rtw_cmd.o] Error 1
make[1]: *** [Makefile:1760: /home/jonathan/Escritorio/RTL8811CU_WiFi_linux/driver/rtl8821CU_WiFi_linux_v5.2.5.3_24795.20171031_COEX20170310-1212] Error 2
make[1]: se sale del directorio '/usr/src/linux-headers-5.4.0-66-generic'
make: *** [Makefile:1893: modules] Error 2
##################################################
Compile make driver error: 2
Please check error Mesg
##################################################

Then I try downloading the driver from this repo: https://github.com/brektrou/rtl8821CU. In order to install it, I just follow the instructions and use dkms. I run the command ls /lib/modules/5.4.0-66-generic/kernel/drivers/net/wireless/realtek/rtl8821cu/ and the 8821cu.ko is there.

Still not working. So the next step is switching my device usb mode. First, I get my device ID using lsusb. ID: 0bda:b812.

Now, when I try to switch the mode, I get an error:

I also have used the command sudo modprobe -r 8821cu but doesn't seems to do nothing.

My pc still not recognizing the adapter if I do iwconfig.

Thanks
Sorry about my English, I'm trying my best.